a users guide for the nasa anopp propeller analysis system
TRANSCRIPT
NASA Contractor Report 4768
A Users Guide for the NASA ANOPP PropellerAnalysis System
L. Cathy Nguyen and Jeffrey J. Kelly
Lockheed Engineering & Sciences ° Hampton, Virginia
National Aeronautics and Space AdministrationLangley Research Center ° Hampton, Virginia 23681-0001
Prepared for Langley Research Centerunder Contract NAS1-96014
February 1997
Printed copies available from the following:
NASA Center for AeroSpace Information
800 Eikridge Landing Road
Linthicum Heights, MD 21090-2934(301) 621-0390
National Technical Information Service (NTIS)
5285 Port Royal RoadSpringfield, VA 22161-2171
(703) 487-4.650
INTRODUCTION TO ANOPP-PAS
Summary
The purpose of this report is to document improvements to the Propeller Analysis
System of the Aircraft Noise Prediction Program (PAS-ANOPP) and to serve as a users
guide. An overview of the functional modules and modifications made to the Propeller
ANOPP system are described. Propeller noise predictions are made by executing a
sequence of functional modules through the use of ANOPP control statements. The most
commonly used ANOPP control statements are discussed with detailed examples
demonstrating the use of each control statement. Originally, the Propeller Analysis System
included the angle-of-attack only in the performance module. Recently, modifications have
been made to also include angle-of-attack in the noise prediction module. A brief
description of PAS prediction capabilities is presented which illustrate the input
requirements neccesary to run the code by way of ten templates. The purpose of the
templates are to provide PAS users with complete examples which can be modified to serve
their particular purposes. The examples include the use of different approximations in the
computation of the noise and the effects of synchrophasing. Since modifications have been
made to the original PAS-ANOPP, comparisons of the modified ANOPP and wind tunnel
data are also included. Two appendices are attached at the end of this report which provide
useful reference material. One appendix summarizes the PAS functional modules while
the second provides a detailed discussion of the TABLE control statement.
111
TABLE OF CONTENTS
.
2.
3.
4.
.
.
.
8.
Page
Introduction ............................................................................. 1
Information Resources .................................................................... 3
Module Documentation ................................................................ 4
Control Statements ..................................................................... 7
4.1 Single Directive Control Statements
4.1.1 ANOPP ....................................................... 8
4.1.2 S TARTCS .................................................... 8
4.1.3 LOAD ......................................................... 8
4.1.4 UNLOAD .................................................... 8
4.1.5 PARAM ...................................................... 8
4.1.6 EVALUATE ................................................. 9
4.1.7 EXECUTE ................................................... 10
4.1.8 ENDCS ...................................................... 10
4.2 Multiple Directive Control Statements
4.2.1 UPDATE ..................................................... 11
4.2.2 TABLE ....................................................... 13
Example Programs
5.1 Generate Module Documentation .......................................... 16
5.2 Generate Atmospheric Data ................................................ 16
5.3 Geometry Module Demonstration ......................................... 17
Module Update
6.1 Propeller Performance Module Modification ............................ 19
6.2 Subsonic Propeller Noise Module Modification ........................ 20
Description of PAS Predictions .................................................... 26
PAS Program Templates
8.1 Blade Geometry
8.1.1 Improved version of PAS .................................. 28
8.1.2 Old version of PAS ......................................... 32
8.2 Prediction of Performance and Loads
8.2.1
8.2.2
8.2.3
8.2.4
Execute the Performance Module without Iteration ..... 38
Execute the Performance Module with Iteration ......... 39
Use PAS Loads for Input .................................. 42
Experimental Loads for Input .............................. 42
iv
9,
10.
Appendix A
Appendix B
8.3 Near-Field Noise Prediction ................................................ 45
8.4 Noise Bubble for Far-Field Noise Prediction ............................ 47
8.5 Flyover Noise Prediction
8.5.1 One Propeller ................................................. 49
8.5.2 Tilt Rotor ..................................................... 51
PAS Prediction and Measured Data
9.1 Results of PAS Studies
9.1.1 Four Methods from SPN ................................... 58
9.1.2 Synchrophasing Using PAS ............................... 58
9.2 Comparison with Measured Data ......................................... 60
References ............................................................................ 62
Functional Modules ......................................... 63
TABLE Control Statement Discussion ................... 64
V
1. Introduction
This document serves as an introduction and guide to the Aircraft Noise Prediction
Program executive system and the Propeller Analysis System (PAS). Elements of this
report such as the executive overview and module documentation are analogous to
reference 1. This report is written for the user who is interested in making propeller noise
predictions on work stations or on main frame computers in batch mode.
It is beneficial for users to understand some of the ANOPP program concepts to be
discussed later in the manual. The ANOPP System is divided into two parts, the Executive
System and the Functional Module Library. A hierarchical representation of ANOPP
components is shown in figure 1. The Executive System controls execution of ANOPP
and consists of several managing routines and a group of general utilities. The purpose of
each major element in the Executive System is listed below
- The Executive Manager controls execution of ANOPP controls statements.
- The Data Base Manager controls activities of data tables and data members.
- The Dynamic Storage Manager allows core sharing and dynamic dimensioning of
variable arrays.
The General Utilities provide access to interpolation routines and other general
functions.
More information concerning the Executive System can be found in reference 2. The
Functional Module Library contains all the subprograms which perform noise prediction
functions.
A flow chart of the ANOPP-PAS system is shown in figure 2. The theory for PAS
is documented in reference 3. To make a propeller noise prediction using the ANOPP-PAS
system, several function modules must be executed in a defined sequence. The procedure
begins by choosing between the original and the improved PAS modules. Originally, PAS
consisted of the Rotating Blade Shape module (RBS), the Blade Section Aerodynamics
module (RBA), and the Blade Section Boundary-Layer module (BLM). New modules
were created to ease inputting the blade geometry and to provide additional compressibility
correction options. In the improved version of PAS, the first letter of each module was
changed to I such as IBS, IBA, IBL. It is suggested that the improved modules of PAS be
used. For an explanation of the improved and modified PAS see reference 4.
The next step in the procedure is to determine the propeller performance. The
Propeller Performance Module (PRP) may be executed several times until the pitch has
converged. If the pitch does not converge, the ANOPP run will be stopped. Otherwise the
next step is to compute the propener loads using the Propeller Loading Module (PLD). The
last step is to calculate the propeller noise using the three noise prediction modules which
are the Subsonic Propeller Noise (SPN), the Transonic Propeller Noise (TPN), and the
Propeller Trailing Edge Noise (PTE) Modules.
PAS allows predictions to be made in several reference frames. For wind tunnel
noise predictions, modules one to six are executed. For flyover noise predictions, modules
one to fourteen are executed. The Atmospheric Module (ATM) and the Atmospheric
Absorption Module (ABS) build the atmospheric table. The flight path is defined by the
Steady Flyover Module (SFO). The Geometry Module (GEO) computes the range and
directivity angles from observer to the noise source. The Tone Propagation module (PRT)
propagates the tone noise from the tone noise modules SPN and TPN and the Broadband
Propagation module (PRO) propagates the broadband noise from the PTE module. The
Noise Level Module (LEV) sums the noise, computes overall sound pressure level
(OASPL), A-weighted sound pressure level, D-weighted sound pressure level, perceived
noise level (PNL), and tone-corrected perceived noise level (PNLT). Effective Noise
Module (EFF) computes effective perceived noise level (EPNL) and sound exposure level
(SEL). A summary of the ANOPP PAS functional modules can be found in Appendix A.
Section 2 contains information resources that can be of aid to users. Module
documentation with examples containing informative comments are the subject of Section
3. Section 4 describes the eleven most often used ANOPP control statements which will
enable the user to set up and execute any ANOPP module. Three examples are provided in
Section 5 which show how to set up a PAS prediction. Section 6 provides a summary of
the improved and updated PAS (third version) which incorporates angle-of-attack in the
noise prediction. A brief description of the capabilities and options of PAS is presented in
Section 7. Section 8 contains ten templates to assist users in building a blade geometry
table, an aerodynamics table such as lift and drag, and to compute the performance and the
loads. Templates for the wind tunnel noise prediction and for the flyover noise prediction
are included. Several templates are provided as examples to help users build a job for
particular purposes. Results of the studies using PAS and the comparison of the measured
data with PAS predictions are shown in Section 9.
The appendices provide supplemental information which will be useful as reference
material. Appendix A is a summary of the functional modules provided in tabular format.
Included in this table is the full title for each module, the associated ANOPP abbreviation,
and a brief description of the function of that module. Appendix B includes a more in-
depth discussion of the TABLE control statement.
2. Information Resources
Fivemanualsareavailablefor usersto obtainmoreinformationabout PAS. The first
document is the Aircraft Noise Prediction Program User's Manual (ref. 5) which contains a
detailed explanation of the ANOPP executive system. The second document is the Aircraft
Noise Prediction Program Theoretical Manual, Part 1 which contains the propagation and
atmospheric absorption models (ref. 6). The third document is Part 3 of the Aircraft Noise
Prediction Program Theoretical Manual which contains the propeller analysis theories,
reference 3. The fourth document is the NASA Aircraft Noise Prediction Program
Improved Propeller Analysis System (ref. 4). This manual describes the modifications and
improvements that were made to the propeller analysis system. For the user who is
interested in making propeller noise predictions without angle-of-attack on an IBM-PC, the
Aircraft Noise Prediction Program Propeller Analysis System IBM-PC Version User's
Manual (ref. 7) is available.
3
3. Module Documentation
User documentation is maintained as a preface to the FORTRAN source code. This
is done to ensure that the correct documentation is available for each version of the program
in existence. This documentation is maintained on line and is accessible to the user.
Figure 3 shows the format for the documentation of each module. The most
important descriptors to the user are the INPUT, OUTPUT, and DATA BASE
STRUCTURE. Under INPUT and OUTPUT, there are user parameters and unit
members. A user parameter retains its value for each execution of a module. A unit
member is closely related to a file and contains a block of data. Unit members will be
discussed in more detail in section 4.2. The DATA BASE Smactures descriptor provides
details concerning all unit members. The ERRORS descriptor provides useful error
diagnostics. Computer core requirement are under LDS _ Dynamic Storage) and GDS
(Global Dynamic Storage).
Example 3.1 depicts user documentation for the Atmospheric Module (ATM).
Included in the documentation are various types of user parameters: integer (1), real single
(RS), and alphanumeric (A). Two examples of table members are included. Example 3.1
will be referred to extensively in Section 4 with further examples demonstrating how to use
the documentation.
Example 3.1 Atmospheric Module Prologue
PURPOSE - BUILD TABLE OF ATMOSPHERIC MODEL DATA AS FUNCTIONSOF ALTITUDE
AUTHOR - SWP(L03KI0/00)
INPUTUSER PARAMETERS
DELHH1
IUNITS
NHO
P1
IPRINT
ALTITUDE INCREMENT FOR OUTPUT, M (FT)GROUND LEVEL ALTITUDE REFERENCED TO SEA LEVELM(FT)INPUT UNITS CODE--2HSI, INPUTS ARE IN SI UNITS=THENGLISH, INPUTS ARE IN ENGLISH UNITSNUMBER OF ALTITUDES FOR OUTPUT ATMOSPHERICFUNCTIONSATMOSPHERIC PRESSURE AT GROUND LEVELN/M**2 (LBF/FT**2)PRINT CODE FOR FORTRAN WRITE0 NO PRINT DESIRED1 INPUT PARAMETER PRINT ONLY2 OUTPUT PRINT ONLY3 BOTH INPUT PARAMETER AND OU'I_UT PRINT
4
tO
tO
tO
tO
tO
tO
tO
tO
tO
tO
tO
tO
tO
tO
tO
tO
tO
tO
tO
tO
tO
tO
tO
tO
_t
tO
REAL USER PARAMETER LIMITS - SI UNITSPARAMETER MINIMUM MAXIMUM DEFAULTDELH 1.0 100000.0 100.0H1 -300.0 10000.0 0.0P1 26200.6517 110000.0 101325.0
REAL USER PARAMETER LIMITS - ENGLISH UNITSPARAMETER MINIMUM MAXIMUM DEFAULTDELH 3.2808 328083.99 328.0839H1 -984.2519 32808.399 0.0P 1 574.212 2297.3978 2116.2167
INTEGER/LOGICAL/ALPHA PARAMETER LIMITSPARAMETER MINIMUM MAXIMUM DEFAULTIPRINT 0 3 3NHO 1 60 1
MEMBER
ATM(_)
TEMPORARIESMEMBER
SCRATCH( TAB1 )
OUTPUTSYSTEM PARAMETER
NERR EXECU'HVE SYSTEM PARAMETER FOR ERROR ENCO_DDURING EXECUTION OF A FUNCTIONAL MODULE. NERRSET TO .TRUE. IF ERROR ENCOUNTERED.
MEMBER
ATM( TMOD )
DATA BASE STRUCTURES
ATM( IN ) CONTAINS DATA INPUT TO ATM IN FOLLOWING FORMAT
RECORD FORMAT DESCRIPTION
1 3RS ALT, TEMP, RELATIVE HUMIDITY(ALTITUDE, "ALT", ISREFERENCED TO SEA LEVEL ANDSHOULD NOT BE LESS THAN USER
PARAMETER H1.)
SCRATCH( TAB1 )
ATM( TMOD )
ALTITUDE UNITSTEMPERATURE UNITSRELATIVE HUMIDITY
M(Fr)KELVlN(RANKINE)PERCENT
TEMPORARY TWO-DIMENSIONAL TYPE 1 DATA TABLEINDEPENDENT VARIABLES
1. ALTITUDE2. ORDERED POSITION
DEPENDENT VARIABLES IN FOLLOWING ORDERTEMPERATUREHUMIDITY
OUTPUT TWO-DIMENSIONAL TYPE 1 DATA TABLE OF
ERRORS
ATMOSPHERIC MODEL VALUES IN DIMENSIONLESS UNITSINDEPENDENT VARIABLES
1. ALTITUDE (REFERENCED TO GROUND LEVEL)2. ORDERED POSITION
DEPENDENT VARIABLES IN FOLLOWING ORDERPRESSUREDENSITYTEMPERATURESPEED OF SOUNDAVERAGE SPEED OF SOUNDHUMIDITY
COEFFICIENT OF VISCOSITYCOEFFICIENT OF THERMAL CONDUCTIVITYCHARACTERISTIC IMPEDANCE(RHO*C)
NON-FATAL
1. USER PARAMETER NHO IS OUT OF RANGE2. MEMBER CONTAINING INPUT DATA NOT AVAILABLE3. LOCAL DYNAMIC STORAGE INSUFFICIENT4. ERROR OCCURRED IN TABLE BUILD ROUTINE WHICH PREVENTED
THE BUILDING OF A TABLE.
5. MEMBER CONTAINING INPUT DATA INVALIDFATAL - NONE
LDS REQUIREMENTS(Maximum Allocation ofLDS - 6190 )
GDS REQUIREMENTS(Maximum Allocation of GDS - 2000 )
6
4. Control Statements
Described in this section are ten of the most frequently used statements for
preparing a PAS module for execution. A complete description of all the ANOPP control
statements can be found in reference 5.
Each executive control statement has a specific format indicated in the following
subsections. All control statement formats adhere to the following conventions:
* Each control statement directive is a free-form sequence, using columns 1 to
80
* A control statement may begin in any column and continue across as many as 5
lines to complete the directive.
* Each control statement is terminated by the $ character.
* Comments may appear in columns following the $ character terminator.
* Comments may continue across lines only if the first character on the line is the
$ character terminator.
The general format of a control statement (CS) is as follows:
CSNAME OPERANDS $ COMMENTS
CSNAME control statement name
Listed below are the twelve most frequently used
ANOPP control statements:
ANOPP STARTCSLOAD UNLOADPARAM EVALUATEEXECUTE ENDCSUPDATE TABLE
OPERANDS These are the operand fields that are required for each
of the individual control statements.
COMMENTS Any user desired comment can be included.
ANOPP control statements can be divided into two categories, Single Directive and
Multiple Directive. As the name implies, single directive control statements require only
one statement to execute a given function. These commands are described in Section 4.1.
Multiple directive control statements, described in Section 4.2, require sub-commands to
execute a given function.
4.1
4.1.1
Single Directive Control
ANOPP Pu _rpose:
Fo_at:
Statements
The ANOPP control statement is the first CS in the
input deck.
ANOPP JECHO=.TRUE. JLOG=.TRUE. $
JECHO: print control during edit phase/LOG: print control during execution phase
A complete list of system parameters has beentabulated on page 3-8 of the ANOPP User's Manualreference 5.
4.1.2 STARTCS Purpose:
Format:
The STARTCS control statement is the second CS in
the input deck. STARTCS begins the execution.
STARTCS $
4.1.3 LOAD Purpose: The LOAD control statement loads unit members
from an ANOPP library which has been previouslystored on an external file via the UNLOAD controlstatement.
Fo_t-
Example:
4.1.4 UNLOAD Puroose:
LOAD/external fileAmitl ..... unim $
Load the unit ATM from the external file LIBRARY.
Unit ATM contains tables which are required by thePRT module.
LOAD/LIBRARY/ATM $
The UNLOAD control statement establishes an
ANOPP library for storage of one or more units onan external file.
Format:
Example:
4.1.5 PARAM Purpose:
Format:
UNLOAD/external file/unit1 ..... unim $
Create an ANOPP library with units UN1 and UN2and store it on external file EXTFIL.
UNLOAD/EXTFK,/UN 1,UN2 $
The PARAM control statement establishes values of
one or more user parameters.
PARAM pnamel=value 1..... pnamen=value n $
4.1.6 EVALUATE
Example:
Purpose:
_o_at"
Ex_mpl¢:
pname:value:
user parameter nameany required integer, real singleprecision, logical, or alphanumeric value
Referring to example 3.1, assign values to thefollowing user parameters:
DELH altitude increment for
output 150. mH1 ground level altitude 10. mNHO number of altitudes for
output atmosphericfunctions 50
IPRINT print option output onlyIUNITS units metric
PARAM DELH=150.,H1=10.,NHO=50,IPRINT=2,IUNITS=2HSI $
The EVALUATE control statement establishes the
value of a user parameter via an arithmeticexpression.
EVALUATE Pnam_xpmssion $
Vname-
expression:user parameter namea sequence of constants, userparameters and functions separated byoperators and parentheses
The arithmetic operators are as follows:
+ addition- subtraction
* multiplication/ division
** exponentiation
It is important to note that the arithmetic operators '+'and '-' must be preceded and followed by at least oneblank space when used in the EVALUATEstatement.
Additional functions are available as shown in Table 1.
Evaluate the nondimensional velocity V given avelocity of 102 meters per second and the defaultspeed of sound, C, equals 340.294 meters persecond.
EVALUATE V=102./C $
Nanle
ABS
ANTtt.OG
COS
INT
LOG
REAL
SIN
Definition
txl
10 x
cos(x)
convert to
integerlogl0(x), x>0
convert to real
sin(x)
Number of
Ar_rnents
Type of
Aq_ments
any typeI,RS,RD
any type
any type
I,RS,RD
any typeany type
Example
Y = ABS(X)y_
ANTILOG(K)
Y = COS(X)
X in degreesY = INT(X)
Y = LOG(X)
Y = REAL(X)
SQRT "(-x, x > 0 1 any type
TAN sin(x)/cos(x) 1 any type Y = TAN(X)
X in degrees
Y = SIN(X)
X indegrees
Y = SQRT(X)
Table 1. Generic Functions for the EVALUATE Control Statement
4.1.7 EXECUTE Purpose:
Fo_at:
Example:
The EXECUTE control statement calls a specificfunctional module into execution.
EXECUTE functional module name $
Execute the Geometry module, GEO.
EXECUTE GEO $
4.1.8 ENDCS Purpose:
Fo_at:
The ENDCS control statement is the last line in theinput deck and terminates the ANOPP run.
ENDCS $
10
4.2 Multiple Directive Control Statements
The control statements discussed so far are single directive statements. The
UPDATE and TABLE statements are multiple directive statements. The purpose of these
two statements is to provide a unit of information to a module.
As indicated in figure 4, a library is a collection of units and a unit is a collection of
members. Two types of members are described, data members and tables. Data members
are input using the UPDATE control statement and provide a unit of information to a
module that does not require interpolation. A unit requiring interpolation is input using the
TABLE control statement. A table is a member with a specific structure.
4.2.1 UPDATE Purpose: The UPDATE control statement allows the user toinput a unit.
Format: UPDATE NEWU=unitname SOURCE=* $
unitname: name of data unit onto which new
members are to be generated
-ADDR Purpose: The -ADDR control statement allows the user to
input a member on a specific unit with the aid of theUPDATE control statement.
Format: -ADDR OLDM=* NEWM=mname FORMAT=format $
mname: input member name
Valid format specifications are:
FORMAT=0 UnformattedFORMAT=2HCI
FORMAT=nHet, .... et$
FORMAT=nH*et ..... et$
Card ImageFixed LengthFormat
Variable LengthFormat
n_ number of Hollerith characters in the
format specification valid element types(et) are:
I IntegerRS Real SingleCS Complex SingleL LogicraA Alphanumeric
The input deck follows the -ADDR statement, isseparated by blanks or commas, and may take asmany lines as necessary.
11
END* Purpose:
Example:
Examole:
Example:
The END* control statement signals the terminationof input to the unit. This statement is also used withthe TABLE and DATA statements.
A user is required to input unit memberOBSERV(COORD) with each record having threereal single precision values.
UPDATE NEWU=OBSERV SOURCE=* $
-ADDR OLDM=* NEWM=COORD FORMAT=4H3RS$
i0. 20. 30. $20. 2O. 2O. $
30. 20. I0. $END* $
A user is required to input unit SFIEI.D whichconsists of members FREQ, THETA, and PHI.This unit member represents the 1/3-octave bandfrequencies, polar directivity angles, and azimuthaldirectivity angles required by every source noisemodule for calculation purposes.
UPDATE NEWU=SFIELD SOURCE=* $
-ADDR OLDM=* NEWM=FREQ FORMAT=4H*RS$50. 63. 80. 100. 125.
160. 200. 250. 315. 400.
500. 630. 800. i000. 1250.
1600. 2000. 2500. 3150. 4000.
5000. 6300. 8000. i0000. $
ADDR OLDM=* NEWM=THETA FORMAT=4H*RS$I0. 30. 50. 70. 90. II0.
150. 170. $
-ADDR OLDM=* NEWM=PHI FORMAT=4H*RS$ $0. $
END* $
A user is required to input unit ATM which consistsof the member IN. This unit member is required asinput to the Atmosphere Module. It consists of atemperature and humidity profile as a function ofaltitude.
UPDATE NEWU=ATM SOURCE=* $
-ADDR OLDM=* NEWM=IN FORMAT=4H3RS$0. 313.2 70. $
i000. 306.7 70. $
2000. 300.2 70. $3000. 293.7 70. $
4000. 287.2 70. $
5000. 280.7 70. $
END* $
$
12
4.2.2 TABLE** Purpose:
Format:
Example 1:
The TABLE control statement builds a table member
in accordance with a set of user supplied instructionsfor interpolation.
Type 1 Tables (only type currently available).
TABLE UNIT(MEMBER) 1 SOURCE--* $INT=0,1,2
IND I=RS,n 1,2,2, independent variable valuesseparated by commas or blanks
IND2=RS,n2,2,2, independent variable valuesseparated by commas or blanks
IND3=RS,n3,2,2, independent variable valuesseparated by commas or blanks
IND4=RS,n4,2,2, independent variable values
separated by commas or blanksDEP=RS, dependent variable values separated by
commas or blanksEND* $
The integer values nl ..... n4 are the number of valuesof the corresponding independent variables. If thetable has less than four dimensions, then fewer
independent variables are needed. If the independentvariable is ordered position, then the RS is replacedby a 0 and no independent variable values areneeded. Independent and dependent variable valuesmay take as many lines as needed.
The following two functions, pressure andtemperature, are input as table ATM(SAMPLE) usingordered position. The tabulated pressure values areentered first followed by the temperature values.IND2 is used to indicate ordered position byreplacing RS with 0 and setting n2 equal to 2indicating the two functions, pressure andtemperature.
Mfimde pressure mm_tmrature0. 2116. 510.
2000. 1965. 506.4000. 1824. 502.6000. 1692. 498.
TABLE ATM (SAMPLE) 1INT=0 1 2
INDI=RS 4 2 2 0.
IND2=0 2 2 2
DEP=RS 2116. 1965.
510. 506.
SOURCE=* $
2000. 4000.
6000.
1824.1692.
502. 498.
** See Appendix B of this manual for a detailed discussion of the TABLE control statement
13
Example 2:
END* $
The following example is a table of the pressure andthe skin friction loadings as functions of thespanwise station (XI1), the chordwise station (XI2),and the in-plane station (PSI). This table is built byPLD or it can be built by the user if the loadinginformation is available. In this table, beside thethree independent variables XI1, XI2, and PSI, thereare two ordered positions: the first one is thepressure loading and the second one is the skinfriction loading.
XI1 XI20.7000 0.00000.8000 1.25660.8500 1.88500.9000 2.51330.9500 3.14160.9750 3.76990.9970 4.3982
5.02655.65496.2832
PSI0.000
The first 70 numbers arc the pressure loadings, andthe next 70 numbers are the skin friction loadings.The table is formed as follows:
TABLE PLD (LOADS ) 1 SOURCE=*
INT= 0 1 2
INDI= RS 7 2 2
0.7000 0.8000 0.8500 0.9000
0.9500 0.9750 0.9970
IND2= RS i0 2 2
0.0000 1.2566 1.8850 2.5133
3.1416 3.7699 4.3982
5.0265 5.6549 6.2832
IND3= RS 1 1 10.0000
IND4= 0 2
DEP= RS
0.0649 0.0718
0.0114 0.0126
-0.1681 -0.1873-0.2728 -0.3350
-0.0724 -0.1310
-0.2257 -0.8863
0.2360 0.2774
0.0501 0.0775
0.1717 0.1965
0 0
0.0907 0.1129 0.1279
-0.1025 -0.1491 0.1600-0.4114 -0.4462 -0.2604
-0.4054 -0.4530 -0.0585
-0.2345 -0.2339 -0.2190
-1.0035 0.1932 0.2041
0.3473 0.3634 0.4279
0.0873 0.0948 0.0905
0.0542 0.0726 0.0842
14
0.0959
0.0441
0.0462
0.0906
0.I000
0.0009
0.0017
0.0015
0.0014
0.0028
0.0025
0.0000
0.0014
0.0027
0.0017
0.0012
O.0025
0.0016
0.0013
END* $
0.1018 0.0654 0.0792 0.0351
0.0517 0.0596 0.0635 0.0385
0.0540 0.0674 0.0745 0.0814
0.0860 0.0933 0.0698 0.0786
0.1251 0.1416 -0.0249 -0.0258
0.0011 0.0013 0.0014 0.0016
0.0023 0.0010 0.0012 0.0014
0.0017 0.0018 0.0025 0.0011
0.0016 0.0017 0.0019 0.0021
0.0014 0.0018 0.0020 0.0023
0.0027 0.0037 0.0000 0.0000
0.0000 0.0000 0.0000 0.0000
0.0018 0.0020 0.0022 0.0025
0.0036 0.0011 0.0014 0.0016
0.0019 0.0021 0.0028 0.0010
0.0014 0.0015 0.0017 0.0018
0.0009 0.0012 0.0013 0.0014
0.0017 0.0023 0.0009 0.0011
0.0014 0.0016 0.0017 0.0023
15
5. Example Programs
In this section, examples will be given showing how to obtain user documentation
for the ATM module and prepare input for execution. The examples include the control
statements necessary to prepare any module for execution.
Example 5.1
To obtain the user documentation for the ATM module, the following ANOPP input
deck can be executed. Appendix A lists the names of modules currently included in PAS-
ANOPP. To obtain user documentation for any one of these modules, replace ATM in the
following example with the name of the desired module.
ANOPP JECHO=. TRUE. $
STARTCS $
LOAD /LIBRARY/ MANUAL $
MEMLIST MANUAL (ATM) FORMAT=2HCI
ENDCS $
The MEMLIST is an ANOPP control statement which allows a user to list the contents of a
unit member. The unit MANUAL contains documentation for all functional modules. The
member ATM contains documentation for the ATM module.
Example 5.2
A demonstration of the use of the Atmospheric Module (ATM) is presented in this
example. The purpose of this module is to generate tables of atmospheric data that can be
used by other modules for subsequent calculations. One table is generated in this example.
This table provides conditions for a standard sea level atmosphere based on a 70% relative
humidity (i.e. 0.2 percent mole fraction). Refer to the Atmospheric Module prologue,
presented as Example 3.1, for more information concerning the input and output of this
module.
ANOPP JECHO=.TRUE. $
STARTCS $
$
$ create the required input data base members$
UPDATE NEWU=ATM SOURCE=* $
-ADDR OLDM=* NEWM=IN FORMAT=4H3RS$ $
0. 288.15 70.
200. 286.85 70.
400. 285.55 70.
16
600. 284.25
800. 282.95
I000. 281.65
END* $
$
$ generate atmospheric properties
$PARAM DELH=I00. HI=0. NH0=II PI=I01325.
$EXECUTE ATM $
$ENDCS $
70. $
70. $
70. $
IPRINT=3 $
Example 5.3
The geometry module (GEO) is executed in this example. For any module to
function properly, it must be supplied with certain tables or units of information. Normally
the data can be generated by one module and then used in subsequent modules. In some
cases, it may be more convenient for the user to provide input data required by a module.
This is accomplished using the UPDATE control statement. For example, when examining
pages 4-5 and 4-6 of the ANOPP User's Manual (ref. 5), it can be seen that the Geometry
Module, GEO, requires the following data base structures: ATM(TMOD), FLI(PATH),
and OBSERV(COORD) as input. The table ATM(TMOD) will be generated using the
Atmospheric Module, ATM. The unit member FLI(PATH) can be generated by the SFO
modules or it can be generated by the user. A detailed description of the unit member
FLI(PATH) is given on page 4-7 of reference 6.
ANOPP JECHO=.TRUE. JLOG=.TRUE. $
STARTCS $
$
$ demonstration problems for geometry module
$
$ create required input data base members$UPDATE NEWU=ATM SOURCE=* $
-ADDR OLDM=* NEWM=IN FORMAT=4H3RS$ $
0. 536.670 50. $
END* $
$PARAM
200
400
600
800
i000
1500
2000
2500
535.957 50. $
535.244 50. $
534.530 50. $
533.817 50. $
533.104 50. $
532.604 50. $
532.236 50. $
532.082 50. $
DELH=I00.
NH0=26
HI=0. UNITS=7HENGLISH
PI=2116.22 IPRINT=3
17
EXECUTE ATM $
$
$
UPDATE NEWU=FLI SOURCE=* $
-ADDR OLDM=* NEWM=PATH FORMAT=5HIORS$ $
0.0 0. 50. -1000. 0.
20.0 700. 50. -1000. 0.
40.0 1400. 50. -1000. 0.
60.0 2100. 50. -I000. 0.
80.0 2800. 50. -1000. 0.
END* $
$
UPDATE NEWU=OBSERV SOURCE=* $
-ADDR OLDM=* NEWM=COORD FORMAT=4H3RS$ $
END* $
$
I00
I00
i000
i000
2000
2000
50 5
0 I0
-50 5
0 I0
I00 5
-I00 i0
$
$
PARAM CTK=I. 0
$
EXECUTE GEO $
$
$
ENDCS $
level flight path and START=I0 and STOP=50
START=I0. STOP=50. $
0. 0. 0. 0. 0. $
0. 0. 0. 0. 0. $
0. 0. 0. 0. 0. $
0. 0. 0. 0. 0. $
0. 0. 0. 0. 0. $
18
6. Module Update
6.1 Propeller Performance (PRP) Module Modification
An error was found in equation (36) of the Aircraft Noise Prediction Program
Theoretical Manual, Propeller Aerodynamics and Noise (ref. 3), page 10.5-9. This
equation computes the resultant velocity of the fluid in the disk plane in the direction of
rotation. Originally the equation was
V_g (r,_) = -[ (r + _ sin 0iv cos _g) (1 - a2) ]
The correct equation becomes
V¥ (r,_g) = -[ (r + k sin otr, sin _) (1 - a2) ]
where r
X
_p
/g
a2
R
spanwise stations, re R
local advance ratio
propeller angle-of-attack, rack
blade rotation angle, rack
induced tangential velocity component, re rR_
blade length
angular velocity of blade, rad/s
Figure 5 shows results from the incorrect equation and the modified equation for
non-zero angle-of-attack. For a zero angle-of-attack simulation no error is involved in the
prediction.
19
6.2 Subsonic Propeller Noise (SPN) Module Modification
ThePASmoduleshavebeencontinuouslyupdated and validated by comparing with
measured data. A major modification was made for inclusion of shaft angle-of-attack in the
Subsonic PropeUer Noise (SPN) module.
NOIVIENCLATUR_
co ambient speed of sound
f function defining blade surface
local force per unit area of blade acting on fluid
£r component of loading vector in direction of of radiation vector, (2, = £i_i )
M some Mach number
M r component of source Mach vector in direction of radiation vector, ( M r = Mi/'i)
n blade surface normal vector
p' acoustic pressure
PL acoustic pressure produced by loading
Pr acoustic pressure produced by thickness
r distance from source point at emission time to observer
unit vector in direction r
S surface area
t time at which noise signal is received by observer
v source velocity vector
V F forward velocity of aircraft
v n source velocity component in direction of blade normal, ( Vn--Vin i )
x observer position in ground fixed frame
y source position in ground fixed frame
ot aircraft angle-of-attack
1"1 source position in blade fixed frame
x time at which noise signal is emitted at source position
Xl/ angle between X1 and rll axes, (xg=_z)
f2 angular velocity of blade
20
SPN Noise Model
Originally, the PAS ANOPP noise module SPN did not include propeller angle-of-
attack (inflow angle) in the module formulation. Modifications were made to SPN to
incorporate the effects due to angle-of-attack and the new version was tested and compared
with DNW data. In the following discussion, the analysis pertains to the Full Blade
Formulation. The physical model on which the module is based expresses the acoustic
pressure as (ref. 3).
4_p__(x,t) = co,] kr(l_M,l -..as+ Jkr (l_M,) dSf=0 f=O
+--1 fV£r(rlV[i_'l'c°Mr-c°M2) 1 dSCo./L r2(1-- Mr) 3 j,f=O
(6.1 a)
where
f4_pr(x,t ) =
f=O
-PoVn (r_tIiri + CoM, -CoM2)]_-S'7.-_- ,3" ./dSr (1- M,) j,
P P
p'(x,t) = PL(X,t) + pT(X,t)
(6.1b)
(6.1c)
Since the integrands depend on vector operations, appropriate reference frames must be
established. Three reference frames, which are illustrated in figure 6, are employed in the
computational scheme. These frames are the ground (medium) fixed x-frame, the aircraft
fixed X-frame and the blade fixed r I -frame. At the initial time, the propeller hub is located
at the origin of the x-frame. The x 3 axis defines the flight direction. Initially, the X-frame
coincides with the x-frame but afterwards translate at the constant rate V F, the aircraft
forward velocity. Operations involving blade normals or surface pressures are more easily
computed in the 11 -frame. But it is more convenient to express the source position, y, in
the x-frame then compute r=x-y and _=r/r in the x-frame and transform the vector
components to the rl -frame. Considering equation (6.1), it is seen that the quantities that
need to be revised to include angle-of-attack are r, [, v n and M. Note that v n and M are
21
based on source absolute velocity. No correction is needed for the source absolute
acceleration, 1_I , since the aircraft forward velocity, VF, is constant. Also, the retarded
time equation (RTE), which must be solved to establish emission time (x) for each
observer time (t), must be modified for angle-of-attack.
The observer and source locations in the x-frame are, respectively
x=VFt+x ° (6.2)
y = VF'C+ T_T_ri (6.3)
where
T.-lsi7cos 0 (6.4)
and
T0t _ cosa0 01 siva ]
-sina 0 cosaj
(6.5)
Thus, the matrix form of equation (6.3) is
IyllEcos cos Y2 = sin_g
Y3 - sin acos_g
-cosasin_ sinai[tit ] I 0 ]
cos sinasinxg cosaJ[_rl3J LvFxJ
(6.6)
Equation (6.6) will be called the fhst correction for a and was implemented in the module
software. For a---O the original component equations are obtained. The above revision for
a allows the radiation vector, given by
r = x-y (6.7)
to be computed in the x-frame. But r must be transformed to the rl -frame for the
calculation of p' according to equation (6.1). This transformation is
22
Erl] Frlr 2 = T_IT_ ' r 2
r3 _ r3 x
(6.8)
where
cosvcosa sin V - cosvsinot-
- sinvcoso_ cos V sinvsina
sin a 0 cos o_
(6.9)
Equation (6.8) represents the second correction for a in the SPN module. The absolute
velocity for each source point is expressed as
V=VF+f2 x rl (6.10)
In the 11-frame, equation (6.10) can be written as
r°lv=T_IT_ 1 0 +f_xT!
LVFJ
(6.11)
From equation (6.11), k is found that the components ofv are
Evl]l vFin c°s lv 2 = :_rl:+ V Fsin ot sin Xlt
v 3 V F coso_
(6.12)
This is the third correction for ct. As indicated in equation (6.1), emission times must be
found for the RTE:
Ix(t) _ y(x)[2= c.2(t _ ,1:)2 (6.13)
Using equations (6.2) and (6.3) allows the above relation to be stated in terms of 1] -frame
components as
23
['Fv_T_l[Xo+ Vr(t-'_)]-B[ 2 = c2(t- _) 2 (6.14)
where
'Fv_'F_ [Xo + VF(t- x)] = T_,_T_='I
Lx3xl]x 2
+ VF(t - x)
(6.15)
Equation (6.14) produces the following retarded time relation
A¢ 2 + B¢ +C + cos(O+D) + EOcos(¢+F) = 0 (6.16)
where
¢ = _('_-t )
2A= Co-
2Tlx*_ 2
B = vF[-x;sina + (x; - rl3)cosa]_2TIX"
C = Ix'2 + r12+ (x; + 11)_]2x'T1
D = W,_-Wx+f_t
V F sin aE =f2x °
F = -V',I +f2t
x_ = x lCosa- x 3sina
x; = x 3cosa+ xlsina
* 4 * 2 2X = X 1 + X 2
24
n - +
This represents the fourth correction for o_. In addition to the Full Blade Formulation, there
are three approximate options in the Subsonic PropeUer Noise module. Corrections for ot
are also included in the mean-surface, compact chord, and point source approximations.
Originally, the SPN iteration procedure had a number of checks, which are
approximations, for the initial guess in Newton's method. If these checks were not
satisfied the program stops and an error message results indicating the TPN module is more
appropriate. This happened for some "non-severe" cases flow RPM, low helical Mach
no.). With the above described coding, no attempt was even made in the Newton iteration
scheme. The code has now been modified to always attempt the iteration. This change
resulted in the previous problematical cases producing plausible sound levels. The TPN
procedure should never be used for a subsonic propeller.
25
7. Description of Prediction Capabilities
ANOPP PAS has the capability of predicting wind tunnel and flyover noise. PAS
noise prediction requires knowledge of the propeller geometry, propeller operating state,
source to observer geometry, and atmospheric data as shown in Table 2.
From the propeller geometry, the Rotating Blade Shape (P, BS or IBS) module
generates a functional representation of the blade surface suitable for aerodynamic and
aeroacoustic calculations. Subsequently, pressure and blade section lift distributions are
computed by the Rotating Blade Aerodynamic (RBA or IBA) module, then blade skin
friction and section drag distributions are computed by the Boundary Layer (BLM or IBL)
module.
There are two options in the Propeller Performance (PRP) module. The first option
is to match the computed power coefficient with the measured power coefficient. An initial
guess of the blade 3/4 radius pitch angle is required for the input. The computed power
coefficient is compared to the measured value. Iteration is performed using the secant
method until the computed and measured power coefficient converge. Thus, the absorbed
power for the predictions match the measured data, but the blade 3/4 radius pitch angles
most likely well differ. The other option is to input the correct 3/4 radius pitch angle and
PRP is executed only one time to compute the absorbed power coefficient. The final blade
pressure and skin friction distributions are determined using the Propeller Loads (PLD)
module.
From the blade geometry and performance data, the propeller noise signature is
predicted by the Subsonic Propeller Noise (SPN) module. This module produces acoustic
time histories and narrow band _ of loading, thickness, and total noise. There are
two options to use SPN. The trn'st option is the noise prediction in a wind tunnel
configuration and the second option is the creation of a noise bubble for further calculation
for a flyover noise prediction. For the wind runnel noise prediction, microphone
(observer) locations are input in rectangular coordinates relative to the propeller hub. For
the noise bubble (flyover prediction) observers are set in the polar and azimuthal directions
with a chosen radius for the noise bubble, The default radius is a distance of five times the
propeller radius. There are four methods which are available in SPN for computing the
radiated acoustic field. They are the full blade surface formulation, mean surface
approximation, compact chord approximation, and point source approximation. Users can
choose one of the four methods depending on the computer execution time and the required
precision of the prediction. Further comparisons of the results of the four methods will be
discussed in Section 9. If the flight Mach number is greater than 0.7, then the Transonic
26
Propeller Noise (TPN) module should be used. The PropcUcr Trailing Edge Noise (PTE)
module computes broadband noise from the propeUer trailing edge.
For flyover predictions, additional calculations are required. Atmospheric
properties are computed from the Atmospheric (ATM) and Absorption (ABS) modules.
The Steady Hyover (SFO) module def'mes the aircraft flight path and the Geometry (GEO)
module computes the range and dircctivity angles from observer to source at sound
emission. The Tone Propagation (PRT) module propagates narrow band spectra from the
source to the observer applying Doppler shift, spherical spreading, characteristic
impedance, atmospheric absorption, and ground effect corrections. The Broadband
Propagation (PRO) propagates the broadband spectra of PTE. The Noise Levels (LEV)
module sums the noise if requested and computes OASPL and LA. Finally, the Effective
Perceive Noise Level (EFF) module computes EPNL.
Table 2. Input data requirements
Propeller Geometry
Airfoil Section CoordinatesChord DistributionTwist Distribution
Leading Edge Displacement DistributionBlade LengthNumber of Blades
Propeller _Operating State
Propeller RPMForward SpeedAbsorbed Power
Root Pitch AngleNacelle Tilt Angle (angle-of-attack)
Source to Observer Geometry
Hight Path AngleObserver Positions
Atmo_hedc Data
Ambient Temperature ProfileGround Level Pressure
27
8. PAS Program Templates
This section contains ten templates which have been developed to demonstrate the
types of problems that can be solved using ANOPP-PAS. Templates one and two
demonstrate how the blade geometry is input using the improved and the original ANOPP-
PAS modules. Templates three and four demonstrate how to compute the propeller
performance. In template three, the blade pitch is known and the performance is computed
directly by the PLD module. In template four, the pitch is unknown and an iterative
scheme is used. Template five demonstrates how the propeller loads are calculated using
the PLD module. Template six demonstrates how measured propeller loads can be input
directly, bypassing the PLD module. Templates seven and eight demonstrate how the
propeller noise is calculated using the SPN module. Template seven calculates the near-
field noise. Template eight calculates the noise on a sphere around the propeller (i.e.
"sound bubble") for propagation to the far-field. Finally, template nine demonstrates a
simple flyover prediction and then template ten demonstrates how ANOPP-PAS can be
used to add noise from multiple rotors such as the tilt rotor. Each template builds upon the
information of the preceding template. The input and output of each module can be found
in reference 3. In most cases this information is also available on line using the "man"
command on UNIX systems and the HELP command on VMS systems. The ANOPP
control statements are described in section 4 of this document. Additional information
concerning the control statements can be found in reference 5.
8.1 Blade Geometry
8.1.1 Template 1 - The Improved Version of PAS
Problem: Given a propeller blade geometry with 5 identical cross sections, tables of
cross sectional lift, drag and pressure coefficients are built in the given ranges of angle-of-
attack and Mach number.
Solution: The fast step is to transform the airfoil section data from Cartesian
coordinate to the elliptical coordinate defined by the inverse Joukowski transformation.
This procedure is performed in IBS. The second step is to compute the sectional lift
coefficient using the Kutta-Joukowski theorem. Also, the pressure coefficient is computed
using Bemoulli's equation. The compressibility con'ection is extended to subsonic flow by
Karman-Tsien or Glauert compressibility corrections in IBA. Finally, the profile drag
coefficient is computed by the method of Squire and Young in IBL.
28
Input thebladegeometryasrequiredin theImprovedBladeShape(IBS) Module. Adescriptionof thebladegeometrycanbe found in reference3. Thebladecrosssectionis
describedin rectangularcoordinates. Chordwise locationsare designatedby x wherex=0.0 is the leadingedgeandequalsx=l.0 is thetrailing edge. The uppersurfacey is
input beforethelower surfacey. Coordinatesx and y arenormalizedby crosssectionchord, c. In this template, there are 5 propeller cross sections with the same spatial
coordinates. The improved modules are used to shorten the input and provides additional
compressibility correction options. Beside the Cartesian coordinates of the cross sections,
other informations about the propeller are required. After showing how many cross
sections are given, the next five lines which have eight numbers in each are
- Spanwise station normalized by the blade radius R
- Leading-edge abscissa as shown in the following plot normalized by R
- Leading-edge ordinate as shown in the following plot normalized by R
- Chord length, normalized by R
- Leading-edge radius, re chord length of the cross section
- Blade twist angle measured positive clockwise looking from hub toward
propeller tip
- Number of x,y pairs for the upper surface
- Number of x,y pairs for the lower surface
An illustration of the blade geometry is shown below.
leading edgeordinate
.,¢"
""r12leading / ....
edg / y .---/ _leading edge ..
......... _S
., ! X
leading edgeabcissa
Til
29
The followings are considerations that users should remember to avoid errors and also to
obtain better predictions.
- The spanwisc stations (XI1), rc R (blade length) array should be in the range of
XI1 in the given blade geometry.
- The chordwise stations (XI2), re 2_, are from 0.0 to 1.0. From 0.0 to 0.5, these
arc points in chordwise direction from trailing edge to leading edge for upper surface. For
lower surface, XI2 is fzom 0.5 to 1.0 from leading edge to wailing edge. For more
accurate results, it is important to refine the grids at the leading edge.
- Blade section angles-of-attack and Mach numbers should be input to adequately
cover the range of the flight condition of the prediction.
ANOPP JECHO=. TRUE. JLOG=.FALSE. $STARTCS $
PARAM R -- 13.205 $ blade radius in ft
PARAM IUNITS = 7HENGLISH $ use English units
UPDATE NEWU=GEOM SOURCE=* $
-ADDR OLDM=* NEWM=BLADE FORMAT=0 $
5 $ five spanwise stations
5 $ five identical airfoil _ections
0.00 -0.0106 0.000 0.043 0.025 0.00 20 19 $ 0%
0.25 -0.0106 -0.000 0.043 0.025 -2.25 20 19 $ 25%
0.50 -0.0106 -0.001 0.043 0.025 -4.50 20 19 $ 50%
0.75 -0.0106 -0.001 0.043 0.025 -6.75 20 19 $ 75%
1.00 -0.0106 -0.002 0.043 0.025 -9.00 20 19 $100%
1.00000
.97000
94000
85000
79000
73000
67000
61000
.55000
.49000
.43000
37000
31000
2500019000
13000
O7OOO
01750
00250
.00000
.00250
.01000
.04000
.00158 $
.00674 $
.01172 $
.02566 $
.03417 $
.04207 $
.04937 $
.05600 $
.06191 $
.06695 $
.07097 $
.07376 $
.07499 $
.07427 $
.07095 $
.06399 $
.05108 $
.02772 $
.01090 $
.o00oo $-.01090 $
-.02130 $
-.04035 $
station
station
station
station
station
3O
END* $
$
$
I0000
16000
22000
28OO0
34000
40000
46000
.52000
.58000
.64000
.70000
.76000
.82000
.88000
.94000
1.00000
UPDATE NEWU=GRID SOURCE =* $
- 05853 $
- 06802 $
- 07298 $
- 07491 $
- 07459 $
- 07254 $
- 06910 $
- 06454 $
- 05905 $
-.05277 $
-.O458O $
-.03819 $
-.02999 $
-.02117 $
-.01172 $
-.0O158 $
END* $
$
$
-ADDR OLDM=* NEWM=XII FORMAT=4H*RS$ $
0.200 0.400 0.600 0.700 0.750
0.850 0.900 0.925 0.950 0.975
-ADDR OLDM =* NEWM=XI2 FORMAT=4H*RS$ $
0 00
0 20
0 41
0 46
0 51
0 56
0 625
0 85
0.025 0.05 0.i0 0.15
0.25 0.30 0.35 0.40
0 .42 0 .43 0 .44 0 .45
0.47 0.48 0.49 0.50
0.52 0.53 0.54 0.55
0.57 0.58 0.59 0.60
0.65 0.70 0.75 0.80
0.90 0.95 0.975 1.00
$
$
$
$
_DATE NE_=IBA SOURCE =* $
-_DR O_M =* NE_=MACH FORMAT=4H*RS$ $
0.I 0.3 0.5 0.7 $
-_DR OLDM =* NE_=ALPHA FORMAT=4H*RS$ $
-6.0 -3.0 0.0 3.0 6.0 5
END* $
0.800
1.000 $
The values of section Mach number and angle-of-attack in degrees
at which the blade section aerodynamics are computed are given here:
Choose the compressibility correction options
EXECUTE IBS $
PARAM ICL = 1 $ Glauert compressibility correction for the lift
$ coefficient
PARAM ICP = 1 $ Glauert compressibility correction for the pressure
$ coefficient
EXECUTE IBA $
EXECUTE IBL $
31
UNLOAD/BLDGEOM/ IBS, IBA, IBL $
ENDCS $
8.1.2 Template 2 - Blade description using the original PAS
modules.
Problem: Given a propeller blade geometry with 8 different cross sections, build
tables of cross sectional lift, drag and pressure coefficients in the given ranges of angle-of-
attack and Math number.
Solution: This template similar to template 1 except it serves as example for the use of
the original RBS, RBA and BLM modules. If IBS, IBA and IBL are preferred then in the
blade geometry input, after the "8 $" line, the next added line is 1, 1, 1, 1, 1, 1, 1, 1 $ to
show that there are 8 different cross sections. Note that the leading edge is input first. The
same resuks are provided as in template 1 except the unit-members or table names should
start with RBS, RBA or BLM instead of IBS, IBA and IBL.
ANOPP $
$STARTCS $
$$$$$
specify 21 evenly spaced chordwise grid points
UPDATE NEWU=GRID SOURCE=* $
-ADDR OLDM=* NEWM=XI2 FORMAT=4H*RS$ MNR=I $
.00 .05 .10 .15 .20 .25 .30 .35
.40 .45 .50 .55 .60 .65 .70 .75
.80 .85 .90 .95 1.0 $
END* $
PARA/_ R=I.0 IUNITS=2HSI $
CREATE GEOM$
UPDATE NEWU=GEOM SOURCE=* $
-ADDR NEWM=BLADE OLDM =* FORMAT=0 $
8 $ NO. OF RADIAL SECTIONS
0.30000 -.05690 .03090 .14375 .02166 28.5
0. 0.0151 $
0.05 0.0475 $
0.I 0.0632 $
15 14 sta 12
32
0.2
0.3
0.4
0.5
0.6
0 7
0 8
0 9
0 925
0 95
0 975
1 0
0 O5
0 1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0. 925
0.95
0.97
1.0
0.45000
O.
0.05
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0. 925
0.95
0.975
1.0
0.05
0.i
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
O. 925
O.95
0.975
1.0
0.60000
O.
0 0846 $
0 0950 $
0 0979 $
0 0950 $
0 0846 $
0 0718 $
0 0544 $
0 0324 $
0 0151 $
0 0116 $
0 0069 $
0 0000 $
-0. 0116 $
-0. 0185 $
-0. 0278 $
-0. 0324 $
-0.0336 $
-0. 0324 $
-0. 0301 $
-0. 0266 $
-0 0220 $
-0 0168 $
-0 0151 $
-0 0116 $
-0 0069 $
0 0000 $
-.06932 .02730
O. 0230 $
0.0466 $
O. O578 $
O. 0702 $
O. O755 $
0.0741 $
0.0689 $
O. 0603 $
O. 0490 $
O. 0364 $
O. 0231 $
O. 0153 $
O. OO82 $
0 0031 $
0 0000 $
0 OO82 $
0 0051 $
0 0021 $
0 $
0 $
0 $
0 $
0 $
0 $
0 $
0 $
0 $
0 $
0 $
-.07300 .02450
O. 0089 $
.16300
.16875
.00919
.00395
21.5
16.9
15 14 $ sta 18
15 14 $ sta 24
33
0.050.i
0.2
0.3
0.4
0.5
0.60.7
0.80.9
0.9250.95
0.975
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0.05
0.10.2
0.3
0.40.5
0.60.7
0.80.9
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O.75000
O.
0.050.1
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0.2
0.3
0.4
0.5
0.6
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0.9
0.925
0.95
0.975
1.0
O. 0281 $
0 0395 $
0 0513 $
0 0553 $
0 0543 $
0 0513 $
0 0454 $O. 0375 $
O. 0286 $0. 0183 $
O. 0148 $
0. 0099 $
O. 0049 $
O. 0000 $0.0029 $
0.0010 $
O. $
O. $O. $
O. $
O. $O. $
O. $o. $
O. $O. $
O. $
O. $-.07450 .02050
0.0033 $
O. 0201 $O. 0281 $
O. 0382 $0.0422 $
0.0427 $0.0412 $
O. 0372 $O. 0312 $
O. 0231 $
O. 0151 $
0.0101 $
o. 0071 $
O. 0O40 $
O. $
O. $0 $
0 $
0 $
0 $
0 $
0 $
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0 $
0 $
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0 $
.16575 .00352 13.5 15 14 $ sta 3O
0.90000
O.
0.05
0.I
0.2
0.3
0.4
0.5
0.6
0.7
0.8
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0.925
0.95
0.975
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0.05
0.1
0.2
0.3
0.4
0.5
0.6
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0.95000 -.06050
O.
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0.3
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0.95
-.06550 .01875
O. 0027 $
0.0189 $
0. 0251 $
O. 0343 $
o.0388 $0 0388 $
0 0365 $
0 0331 $
0 o280 $0 0217 $
0 0143 $
0 0103 $
0 0046 $
0 0023 $
o $o $o $o. $o. $o. $o. $o. $o. $o. $o. $o. $o. $o. $o. $
.01725
O. 0027 $
O. 0189 $
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0.0388 $
0.0388 $
O. 0366 $
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o.0280 $O. 0217 $
0. 0143 $
0. 0103 $
O. 0046 $
0. 0023 $
O. $
o $o $o $o $0 $o $o $o $o $o $o $0 $
.14575
.13438
.00286
.00286
ii.i
10.45
15 14 $ sta 36
15 14 $ sta 38
35
0.975
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0.97500
O.
0.05
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0.2
0.3
0.4
0.5
0.6
0.7
0.8
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0.95
0.975
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0.1
0.2
0.3
0.4
0.5
0.6
0.7
0 8
0 9
0 925
0 95
0 975
1 0
0.99750
O.
0.05
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0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0.925
0.95
0.975
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0.05
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0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
O. $
O. $
-.05250 .01750
O. 0O20 $
0. 0178 $
0. 0244 $
0. 0311 $
0. 0340 $
O. 0355 $
0. 0340 $
0. 0304 $
0. 0259 $
0.0200 $
O. 0133 $
O. 0074 $
0.0029 $
0.0015 $
0 $
0 $
0 $
0 $
0 $
0 $
0 S
0 $
0 $
0 $
0 $
0 $
0 $
0 $
0 $
-.0125 .00925
O.002 $
0. 0178 $
0 0244 $
0 0311 $
0 0340 $
0 0355 $
0 0340 $
0 0304 $
0 0259 $
O. 0200 $
O. 0133 $
O. 0074 $
0.0029 $
O. 0015 $
O. $
O. $
O. $
O. $
O. $
O. $
O. $
O. $
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I0.12
9.83 15
15 14 $ sta 39
14 $ sta 39.9
36
0. 925 0. $0.95 0. $0.975 0. $1.0 0. $
END* $
compute smooth blade shape using RBS module
EXECUTE RBS $
compute blade aerodynamics with RBA & BLM module
EVALUATE R = 40. * .0254 $ convert inches to meters
PARAM VNU = .17894E-04 CA= 340.29 $
EVALUATE RINF = CA * R / VNU $
PARAM IPRINT=3 NORDER=4 $
CREATE REA$
UPDATE NEWU=RBA SOURCE=*
-ADDR NEWM=MACH OLDM = *
.I 3 5 7
-ADDR NEWM=ALPHA OLDM =*
-6. -3. 0.0 3.
END*$
$FORMAT=4H*RS$ MNR=I$
$FORMAT=4H*RS$ MNR=I$
6. $
EXECUTE RBA $
EXECUTE BLM $
UPLIST $
save the tables created up to this point on file BCPLIB
UNLOAD /BCPLIB/ RBS,RBA, BLM $
ENDCS $
37
8.2 Prediction of the Performance and Loads
PRP.
Templates 3 and 4 are examples of the use of PRP. There are 2 options to run
- The first option is to input the correct root pitch angle then PRP will compute the
power coefficient and other parameters.
- The second option is to input measured power coefficient and an initial guess of
blade pitch which is computed as follows:
fleta75 = tan -1 1t".f_r75
An iterative process is required to obtain the correct root pitch angle to match the
measured power. PRP is executed until the computed power coefficient and the measured
value match. If measured loads are used for the noise prediction instead of the PAS
predicted loads, a table PLD0.,OADS) is required. Templates 5 and 6 are examples for
computing the loads and using the measured loads table.
8.2.1 Template 3 -Execute the Performance Module without
Iteration Process
Problem: Given the specified flight condition and a library which contains the blade
geometry and the sectional lift and drag for set ranges of Mach number and angle-of-attack,
compute the induced axial and angular velocities, inflow angle, resultant velocities, power
coefficient, thrust coefficient, advance ratio, propeller efficiency, local angle-of-attack, and
local Mach number.
Solution: The blade element-momentum theory with two-dimensional aerodynamic
characteristics of the axially symmetric inflows and induced velocities is used in PRP. In
this template, since the blade pitch setting is known, no iterative process is required. The
input blade geometry and the lift and drag coefficient tables are stored in a library named
BCPLIB which is created from template 2. These tables are used as interpolation tables for
a specified flight condition. This specified operating condition has to be in the ranges of
angle-of-attack and Mach number computed in template 2.
38
ANOPP $
STARTCS $
LOAD /BCPLIB/ RBS RBA BLM $
PARAM ALPHAP = 0.
PARAM IDPDT = 0
PARAM BETA75 = 19.9
PARAM VF = 51.2
PARAM ORIG = 13.5
EVALUATE BETA = BETA75
EVALUATE THETAR = BETA *
EVALUATE ALPHAP = ALPHAP
PARAM MACHRF = 0.69
PARAMMZ = 0.26
EXECUTE PRP $
ENDCS $
$ set propeller angle-of-attack in degrees
$ propeller loading is steady
$ propeller 3/4 span pitch angle in degrees
$ flow velocity in m/s
$ blade twist angle at 3/4 span in degrees
$ (obtain from the blade geometry at 3/4
$ span)
- ORIG
$ compute root pitch in degrees
PI / 180.
$ convert root pitch to radians
* PI / 180.
$ convert propeller angle-of-attack to
$ radians
$$
8.2.2 Template 4 - Execute the Performance Module withIteration Process
Problem: The power input is known. The blade geometry and the lift and drag
coefficient tables are provided from template 1. Compute the performance and find the
correct root pitch angle in the specified operating condition.
Solution: This template is the same as template 3. The difference is the power input is
known in this problem when the root pitch setting is known in template 3. An iterative
process is required to find the correct root pitch angle. PRP is executed until the computed
power coefficient matches the measured power coefficient.
ANOPP JECHO=.TRUE. JLOG=.FALSE.
STARTCS $
$$$$$$$
LENGL=20000 $
this run predicts the noise for the FAA DNW wind tunnel propeller
tests. It applies a correction to the propeller blade pitch to
match the measured power.
the following parameters set the tunnel and propeller operating
39
$ conditions:
$$PARAM ALPHAP = 0.
PARAM IDPDT = 0
PARAM BETA75 = 19.9
PARAM RPM = 2100.
PARAM TEMP = 15.6
PARAM POW = 95.9
PARAM VF = 51.2
$ set propeller angle-of-attack in degrees
$ propeller loading is steady
$ initial guess for propeller 3/4 span pitch$ angle in degrees
$ propeller rpm
$ temperature in degrees Celsius
$ measured power in kilowatts
$ flow velocity in m/sEVALUATE
PARAM ORIG = 13.5
PARAM RHOA = 1.194
PARAM IUNITS = 2HSI
PARAM IPRINT = 1
PARAM IMPROV = .TRUE.
$$
R = 40./12. $ blade length in meters
$ blade twist from root to 3/4 span
$ ambient density in kg/m**3$ metric units
$ request input and output print
$ use the improved version of PAS
$ blade shape is specified by loading library /BLDGEOM/$$
LOAD /BLDGEOM/ IBS IBA IBL $
$$
$ evaluate control statements are used to compute additional required$ quantities
$$EVALUATE
PARAM
EVALUATE
EVALUATE
EVALUATE
EVALUATE
RPS = RPM / 60. $ compute revolutions per second
PI = 3.1415926 $ set value of pi
R = R * 0.3048 $ radius in meter/sec
D = R * 2. $ compute propeller diameter
CPREF = POW / RHOA / RPS**3 / D**5
$ compute power coefficient
BETA = BETA75 - ORIG
$ compute root pitch in degreesEVALUATE THETAR = BETA * PI / 180.
$ convert root pitch to radiansEVALUATE ALPHAP = ALPHAP * PI / 180.
$ convert propeller angle-of-attack to radiansEVALUATE TA = 1.8 * TEMP + 32.
$ convert temperature in degrees Celsius to$ degrees Fahrenheit
EVALUATE CAE = 49. * SQRT ( TA + 459.6 )
$ compute speed of soundEVALUATE CA = CAE * .3048
$ speed of sound in meter/sec
EVALUATE MZ = VF / CA
$ compute forward mach number
EVALUATE OMEGA = 2. * PI * RPS
$ compute angular velocityEVALUATE MACHRF = R * OMEGA / CA
$ compute rotational tip Mach number$$
$ the computational grid on the blade surface is now defined$
4O
$
UPDATE NEWU=GRID SOURCE=* $
-ADDR OLDM=* NEWM=XII FORMAT=4H*RS$ $
0.30 0.35 0.40 0.45 0.50 0.55
0.70 0.75 0.775 0.80 0.825 0.85
0. 925 0.95 0. 975 0. 997 $
-ADDR OLDM=* NEWM=XI2 FORMAT=4H*RS$ $
0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35
0.425 0.45 0.46 0.47 0.475 0.48 0.485 0.49
0.505 0.51 0.515 0.52 0.525 0.53 0.54 0.55
0.625 0.65 0.70 0.75 0.80 0.85 0.90 1.00
-ADDR OLDM=* NEWM=PSI FORMAT=4H*RS$ $
0.00 $
END* $
0.60
0.875
0.65
0.90
0.375 0.40
0.495 0.50
0.575 0.60
$
the 3/4 span blade pitch must be adjusted so that the computed power
coefficient matches the measured power. This requires an iterative
solution in the propeller performance (PRP) module. The secant method
is used to find the root to the equation F(Z) = CPREF - CP
convergence is assumed when the computed value is within one percentof the measured value.
PARAM Z1 = THETAR $
EXECUTE PRP $
EVALUATE FZI = CPREF - CP $
EVALUATE THETAR = THETAR + PI / 180. $
PARAM Z2 = THETAR $
PARAM COUNT = 1 $
LAB1 CONTINUE $
EXECUTE PRP $
EVALUATE FZ2 = CPREF - CP $
EVALUATE DIFF = FZ2 / CPREF $
EVALUATE DIFF = ABS(DIFF) $
EVALUATE COUNT = COUNT + 1 $
IF ( DIFF .LT. 0.01 ) GOTO LAB2 $
EVALUATE Z = Z2 - FZ2 * ( Z2 - Zl ) / ( FZ2 - FZI ) $
PARAM Z1 = Z2
PARAM Z2 = Z
PARAM FZI = FZ2
PARAM THETAR = Z
EVALUATE COUNT = COUNT + 1
IF ( COUNT .GT. 10 ) GOTO LAB3
GOTO LAB1
LAB2 CONTINUE
UNLOAD /PRPLIB/
GOTO LAB4
LAB3 CONTINUE
LAB4 CONTINUE
ENDCS $
41
8.2.3 Template 5 - Use PAS to Compute Loads
Problem: From the blade shape and the performance libraries, compute the pressure and
friction loadings for the noise prediction.
Solution: This template is an example of computing the loads using ANOPP PAS.
The input for the PLD module are the blade shape and the performance libraries which are
created by the blade shape, aerodynamic, boundary layer, and propeller performance
modules. PLD is executed to create a load table based on blade element theory together
with two-dimensional aerodynamic characteristics.
ANOPP JECHO=.TRUE. JLOG=.F ALSE. LENGL=20000 $
STARTCS $
$$$ blade shape is specified by loading library /BLDGEOM/
$$LOAD /BLDGEOM/ IBS IBA IBL $
$$ load the performance results
$LOAD / PRPLIB/ $
$$ the following parameters set the tunnel and propeller operating
$ conditions:
$$PARAM NBLADE = 2
PARAM IUNITS = 2HSI
PARAM IPRINT = 3
PARAM IMPROV = .TRUE.
$$EXECUTE PLD
$UNLOAD /PLDLIB/ $
$
$ number of propeller blades
$ metric units
$ request input and output print
$ use the improved version of PAS
$ compute loads
ENDCS $
Problem:
template 1.
8.2.4 Template 6 - Experimental Loads for Input
Compute the noise for 2 observers from measured loads for the propeUer in
42
Solution: This is an example of inputting a loads table for the noise prediction instead
of computing the loads in PAS. A loads table as a function of spanwise station, chordwise
station, and in-plane angle is constructed for the input. Note that there are two order
position parameters. The first one is the pressure loading and the second one is the skin
friction loading.
ANOPP $
STARTCS $
s$ create table PLD(LOADS)
$TABLE PLD (LOADS )
INT = 0 1 2
INDI = RS 9 2 2
0.50OO O.60OO O.7O00
0.9750 0.9970
IND2 = RS 12 2 2
0.0000 1.2566 1.8850
3.1730 3.7071 4.3982
IND3 = RS 1 1 1
0.0000
IND4 = 0 2 0 0
DEP = RS
0.0607
0.0126
-0.4114
-0.4530
-0.2190
0. 0492
0.0997
0 1932
0 1962
0 0307
0 1141
0 0654
0 0635
0 1251
0.0013
0.0012
0.0011
0.0011
0 .O005
0.0018
0.0007
0.0000
0.0008
0.0021
0.0014
0.0010
0.0007
END* $
S
0.0728
-0.0492
-0.4462
-0.0585
-0.2257
0.1350
0.1426
0.2041
0.1907
0.0412
0.0069
0.0792
0.0385
0 1416
0 0014
0 0014
0 0014
0 0014
0 0006
0 0003
0 0009
0 0000
0 0008
0 0024
0 0016
0.0012
0.0009
0 0649
-0 0531
-0 1942
-0 0724
-0 8863
0 1945
0 2062
0 2360
0 2084
0 0617
0.0399
0.0206
0.0462
-0.0249
0.0016
0.0015
0.0016
0.0018
0.0009
0.0003
0.0000
0.0000
0.0009
0.0026
0.0017
0.0014
0.0011
1 SOURCE =* $
0.8000 0.8500 0.9000 0.9500
2.5133 3.0788 3.1102 3.1416
5.0265 6.2832
0 0718
-0 1025
-0 2881
0 0O65
-I 0035
0 3967
0 2709
0 2774
0 2471
0 0869
0 0542
0 0296
0.0625
-0.0258
0.0017
0.0017
0.0017
0.0020
0.0012
O.OO04
0.0000
0.0003
0.0012
0.0029
0.0019
0.0015
0.0013
0.0907
-0.1491
-0.2604
-0.0038
0 1491
0 4376
0 3801
0 3473
0 2947
0 1035
0 0726
0 0351
0 0775
0.0005
0.0023
0.0018
0.0019
0.0023
0.0014
0.0006
0.0000
0.0004
0.0009
0.0039
0.0021
0.0017
0.0014
0.1129 0
-0.1600 -0
-0.2728 -0
-0.1310 -0
0.1935 0
0.1501 0
0.4327 0
0.3634 0
0.3547
0.1190
0.0842
0.0441
0.0698
0.0007
0.0006
0.0025
0.0021
0.0025
0.0016
O.OOO7
0 0000
0 OOO5
0 0012
0 00O7
0 0028
0 0018
0 0016
.1279
.1681
.3350
.2345
.0759
.1947
.1511
.4279
0.0334
0.1158
0.0959
0.0517
0.0786
0.0009
0.0008
0 0007
0 0028
0 0027
0 0017
0 0008
0 0000
0 0006
0.0015
0.0009
0.0006
0.0025
0.0017
0.0114
-0 1873
-0 4054
-0 2339
-0 0047
0 1345
0 1960
0 1484
0 1229
0 0855
0 1018
0 0596
0 i000
0 0011
0 0010
0 0009
0 0009
0 0037
0 0013
0 0009
0 0000
0.O007
0.0019
0.0011
0.0008
0.0005
0.0023
43
$$$$LOAD /BLDGEOM/
$$
load the blade shape library
PARAM IMPROV = .TRUE
PARAM R = 1.016
PARAM NBLADE = 2
PARAM RHOA = 1.194
PARAM CA = 340.0
PARAM RPM = 2100
PARAM VF = 51.2
PARAM THETAR = 0.1292
PARAM NHARM = 20
PARAM NTIME = 512
PARAM IUNITS = 2HSI
PARAM IATM = 0
PARAM IOUT = 0
PARAM PI = 3.1416
$ use the improved version of PAS
$ blade length in meters
$ number of propeller blades
$ ambient density in kg/m**3
$ speed of sound in m/s
$ propeller rpm
$ flow velocity in m/s
$ root pitch angle in tad.
$ number of harmonics desired
$ number of time points for waveform
$ metric units
$ atmospheric data from user parameters
$ no output unit member
$
EVALUATE RPS = RPM / 60. $ revolutions per second
EVALUATE MZ = VF / CA $ compute forward Mach number
EVALUATE OMEGA = 2. * PI * RPS
$ compute angular velocity
EVALUATE MACHRF = R * OMEGA / CA
$ compute rotational tip Mach number
$
$ observer positions are defined for the two observers of interest
$
UPDATE NEWU=OBSERV SOURCE=* $
-ADDR OLDM z* NEWM=COORD FORMAT=4H3RS$ $
4.453 0. 2.571 $ observer 1 30 degrees
4.000 0. 0. $ observer 2 0 degrees
END* $
EXECUTE SPN $
ENDCS $
44
8.3 Template 7 - Near-Field Noise Prediction
Problem:
respect to the propeller hub given by
4.453 m 0. m 2.571m
4.000 m 0. m 0. m
at the following operating condition:
propeller RPM =
number of blades =
blade length =
inflow velocity =
root pitch angle =
Predict the noise for the two observers having x,y,z coordinates with
observer 1
observer 2
2100
2
1.016 m
51.2 m/s
0.1292 rad.
Solution: The blade geometry and the blade surface pressure are known from template
1 and template 5. The computation of the periodic acoustic pressure signature and the
spectrum of the propeller with subsonic tip speed are based on a solution of the Ffowcs
Williams-Hawkings equation without the quadrupole source term. The observers are
assumed to be moving with the aircraft and the full blade approximation is used in this
prediction.
ANOPP $
STARTCS $
$
$ observer positions are defined for the two microphones of interest
$UPDATE NEWU=OBSERV SOURCE =* $
-ADDR OLDM=* NEWM=COORD FORMAT=4H3RS$ $
4.453 0. 2.571 $ observer 1 30 degrees from propeller plane
4.000 0. 0. $ observer 2 0 degrees or in the propeller plane
END* $
$
$ blade shape is specified by loading library /BLDGEOM/
$LOAD /BLDGEOM/ IBS IBA IBL $
$
$ Pressure and skin loadings
$UNLOAD /PLDLIB/ $
$PARAM IMPROV = .TRUE $
PARAM R = 1.016 $
PARAM NBLADE = 2 $
PARAM RHOA = I. 194 $
PARAM CA = 340.0 $
PARAM RPM = 2100 $
in the /PLDLIB/ library
blade length in meters
number of propeller blades
ambient density in kg/m**3
speed of sound in m/s
propeller rpm
45
PARAM VF = 51.2
PARAM THETAR = 0.1292
PARAM NHARM = 20
PARAM NTIME = 512
PARAM IUNITS = 2HSI
PARAM IATM = 0
PARAM IOUT = 0
PARAM PI = 3.1416
$ flow velocity in m/s
$ root pitch angle in rad.
$ number of harmonics desired
$ number of time points for waveform
$ metric units
$ atmospheric data from user parameters
$ the default value for iout is 0. For near
$ -field noise prediction, iout=0 or iout=2
$ and OBSERV(COORD) are required. If
$ SPN(FFT) and SPN(TIME) are required, then
$ iout=2
$EVALUATE RPS = RPM / 60.
EVALUATE MZ = VF / CA
$ revolutions per second
$ compute forward mach number
EVALUATE OMEGA = 2. * PI * RPS $ compute angular velocity
EVALUATE MACHRF = R * OMEGA / CA
$ compute rotational tip Mach number
PARAM METHOD = 1 $ full blade surface approximation
EXECUTE SPN $
ENDCS $
46
8.4 Template 8 - Noise Bubble for Far-Field Noise Prediction
Problem: This problem is similar to the problem in template 7 with the exception that
observer coordinates are input in the spherical format. In this example, the observers are
on the plane perpendicular to the propeller plane starting from the flight direction to the
back of the propeller at the following angles:
10o 30° 50 ° 90° 120 ° 150 ° 179 °
Source radius = 5 * R where R is the propeller radius
Solution: The same computational method is used in template 7. In this template,
observers are defined on an imaginary bubble which is specified by a constant radius, polar
directivity angles, and the azimuthal angles. The polar directivity angle is specified from
the front of the propeUer (0 °) to the back of the propeller (180 °) in the inflow direction. The
azimuthal angle is determined from the left hand side to right hand side of the propeller
specified from the inflow direction looking toward the propeller. A noise table is created
on the bubble which is used later by way of interpolation to evaluate the noise at specified
observers on the ground. It is important to set the parameter IOUT=2 and to input the unit
member SFIELD(THETA) and SFIELD(PHI). The source radius RX, re R is also
required.
ANOPP $
STARTCS $
$$ the sound field arrays must be defined.
$ chosen only on the propeller plane
$UPDATE NEWU=SFIELD SOURCE =* $
-ADDR OLDM=* NEWM=THETA FORMAT=4H*RS$ $
10. 30. 50. 90. 120. 150. 179.
-ADDR OLDM=* NEWM=PHI FORMAT=4H*RS$ $
0. .i .2 .3 .4 .5 .6 .7 .8 .9
In this case observers are
$
I. $
END* $$$ additional output control
$PARAM IATM = 0
PARAM IOUT = 1
PARAM IDPDT = 1
PARAM ALPHAP = 0.020
PARAM R = 1.016
PARAM MZ = 0.157
PARAM THETAR = 0.0576
PARAM MACHRF = 0.649
PARAM CA = 342.5
PAKAM RHOA = 1.162
parameters are required
$ use atmospheric user parameters
$ generate farfield noise table in SPN
$ unsteady because of angle-of-attack
$ propeller angle-of-attack in radians
$ blade length in meters
$ flight Mach number
$ root pitch angle in radians
$ rotational tip Mach number
$ speed of sound in meters/sec
$ density in kg/meters**3
47
$$ the blade shape library is BLDGEOM and the load library is PLDLIB$
LOAD / BLDGEOM/ $
LOAD /PLDLIB/ $
$
EXECUTE SPN $
UNLOAD /SPNLIB/ $
ENDCS $
48
8.5 Flyover Noise Prediction
8.5.1 Template 9 - One Propeller
Problem: Given observers on the ground, predict the noise for the observers when the
aircraft is at a level flyover with the following operating conditions:
Aircraft speed = 51.2 m/s
Flight path angle = 6.2 °
Altitude = 211.5 m
Propeller angle-of-attack = 1.15 o
The propeller operating condition is the same as template 8.
Solution: Amaospheric properties for the given altitude will be determined from using
the standard atmospheric table. This table is in PROCLIB library as shown below.
The first step is to create a noise buble as it was done in template 8. The second
step is to find the position of the noise source as function of time in the Steady Fly Over
(SFO) Module. The third step is to execute GEO to establish the vectors from the source to
the observer. The output from GEO includes the polar directivity angle, the azimuthal
angle, and the elevation angle as functions of reception time. The fourth step is to execute
PRT. PRT will sum the noise at the same frequencies if there are more than one noise
source (correlated). Then the noise is computed at the observer location with information
provided by the GEO module. Doppler shift, spherical spreading, and characteristic
impedance effects are always included in the calculations. Options are available for
atmospheric absorption and ground effects. Module LEV computes noise metrics (A-
weighted, etc.). Lastly, the Effective Noise Module (EFF) computes EPNL if requested.
ANOPP $
STARTCS $
$$ standard atmosphere is
$ library
$$LOAD /LIBRARY/ PROCLIB
CALL PROCLIB (ATMSTD)
LOAD /SPNLIB/
$
loaded from system library load the noise
$ the flight path is now defined using the steady flyover module
$PARAM VF = 51.20 $ aircraft speed in m/s
PARAM PATHANG = 6.2 $ flight path angle in degrees
PARAM VI = VF $ set forward speed
PARAM ENGNAM = 3HXXX $ set member name parameter
49
PARAM
PARAM
PARAM
EVALUATE
PARAM
EVALUATE
PARAM TF = I0.
EVALUATE XF = TF * VI
PARAM ZF = ZI
PARAM ALPHA = 1.15
$
TI = -20. $ set start time in seconds
TSTEP = 1.0 $ set time step in seconds
THW = PATHANG $ set path angle
XI = TI * VI $ compute starting x position
YI = 0. $ set starting y position
ZI = 211.5 + XI * SIN(THW)
$ compute starting z position
$ set final time in seconds
$ compute final x position
$ final z position
$ propeller angle-of-attack in degrees
$ execute SFO module using default values for remaining parameters$EXECUTE SFO $
$$
$ reset parameters for geometry module$
PARAM START = -20.
PARAM STOP = TF
PARAM DELT = 0.5
PARAM DELDB = 20.
PARAM
$$
ICOORD = 1
$ start time in seconds
$ ending time in seconds
$ reception time increment in seconds
$ limiting noise level, down from the
$ peak (dB)
$ request body axis output only
The remaining parameters use default values. The location of the
observers are input in meters referenced to the point 2500 meters
from brake release. The first microphone (observer) position is at
that point. The second observer position is at 1890 meters from
brake release which corresponds to an X coordinate of -610 meters.
Both flush and 1.2 meter microphones were used.
The observer input member is:
UPDATE NEWU=OBSERV SOURCE=* $
-ADDR OLDM=* NEWM=COORD FORMAT=4H3RS$ $
0. 0. 0. $0. 0. 1.2 $
-610. 0. 0. $
-610. 0. 1.2 $
END* $
$
$ execute geometry module$
EXECUTE GEO $
$
$ now, the parameters are defined for the tone propagation (PRT)$ module
$PARAM R = 1.016
PAKAM RX = 5.
PARAM NBLADE = 2
PARAM RPM = 2100.
EVALUATE RPS = RPM / 60.
EVALUATE DELF = RPS * NBLADE
primary mic - ground
primary mic - 1.2 meter
secondary mic - ground
secondary mic - 1.2 meter
$ blade in meters
$ pick source radius to be 5
$ propeller radii
$ number of blades
$ propeller rpm
$ compute revolutions/second
$ bandwidth is blade passing
50
EVALUATE RS = RX * R
PARAM SURFACE = 4HSOFT
PARAM ABSORP = .TRUE.
PARAM GROUND = .TRUE.
$
$ frequency
$ convert to dimensional source
$ radius
$ soft boundary
$ predict standard absorption effect
$ predict ground effects
$ tone propagation module is executed with remaining parameters
$ defaulted
$EXECUTE PRT YYYYYY=SPN GEOM=BODY $
$
$ the noise levels module (LEV) is executed to compute frequency
$ integrated levels. Only narrow band levels are computed.
$PARAM NAWT=.TRUE. NDWT=.TRUE. NOSPL=.TRUE.
$ set narrow band level flags to true
PARAM IAWT=.FALSE. IDWT=.FALSE. IOSPL=.FALSE. IPNL=.FALSE.
IPNLT=.FALSE. $ set I/3-octave band level flags to false
PARAM MEMSUMN=4HPRT 4HPRES
$ define input member
$$ the lev module is now executed
$EXECUTE LEV $
$EXECUTE EFF $
$
ENDCS $
8.5.2 Template 10 - Tilt Rotor
Problem: Predict the noise for the tilt rotor in propeller mode. This tilt rotor has two
identical propellers, the NACA 16 airfoil. The aerodynamic information such as lift and
drag coefficients are built in the library NACALB. The operating conditions are
Flight altitude = 250 ft
Indicated airspeed = 150 knots
Number of blades = 4
Propeller radius = 4 ft
Propeller RPM = 1550.
Distance from each propeller hub to the centerline of the aircraft is 12.5 ft
Solution: This example is a flyover noise prediction for a tilt rotor in the propeller
mode. SPN creates a noise bubble for each propeller. A common point between the two
51
propellersis chosen. The MSN module sums the noise of the two propellers at a common
point. The trailing edge noise for each propeller is also computed from PTE. After SFO
establishes the source location, GEO estabhshes the source to observer geometry, PRT
propagates the tone noise from MSN and PRO propagates the broad band noise from PTE
to chosen observers on the ground. Then LEV sums the total noise.
ANOPP $
STARTCS $
$$ .....
USER INPUT PHASE OF RUN
$PARAM ALT = 250.
PARAM VIAS = 150.
PARAM VGS = 150.0
PARAM TILT = 0.
PARAM PSI = 180
PARAM IUNITS = 7HENGLISH $
PARAMNBLADE = 4 $
PARAM RADIUS = 4.00 $
PARAM IPRINT = 1 $
$
$ altitude in feet
$ indicated airspeed in knots ( this
$ should be changed to true airspeed when
$ it is available )
$ ground speed in knots
$ nacelle tilt angle in degrees
$ direction of flight ( affects microphone
$ numbering )
English units are being used
four propeller blades
propeller radius in feet
turn off output print to save paper
$ NACALB is the blade shape library which was created from the
$ execution of IBS, IBA, and IBL from using NACA 16 airfoil.
$ The standard atmospheric table in the library named LIBRARY
$$
LOAD /NACALB/ $
LOAD /LIBRARY/ ATM=ATMOS (AAC=ABS TMOD=STRD) $
$$
$ the propeller positions are defined for the multirotor source noise
$ module so the acoustic interaction effects between the propellers can
$ be determined. Note that change from propeller to rotor coordinates
$ does not affect this input
$
PARAM Xl = 0. 12.500 0. $ position of first propeller
PARAM X2 = 0. -12.500 0. $ position of second propeller
$$
-----$
COMPUTATIONAL GRIDS
-$$
$ the directivity angle and observer position data are entered here.
$ The standard ANOPP grids are used.
$
$UPDATE NEWU=SFIELD SOURCE =* $
-ADDR OLDM=* NEWM=THETA FORMAT=4H*RS$ $
52
i0. 30. 60. 90. 120. 150. 179. $
-ADDR OLDM=* NEWM=PHI FORMAT=4H*RS$ $
-90. -75. -60. -45. -30. -15. 0.
15. 30. 45. 60. 75. 90. $
-ADDR OLDM=* NEWM=FREQ FORMAT=4H*RS$ $
12.5 16. 20. 25. 31.5 40. 50. 63. 80.
100. 125. 160. 200. 250. 315. 400. 500. 630.
800. 1000. 1250. 1600. 2000. 2500. 3150. 4000. 5000.
6300. 8000. 10000. $
END* $
$
$ define microphone positions based on flight direction$IF ( PSI .EQ. 0 ) GOTO LAB10 $
$
$ microphone definitions for 180 degree direction of flight (start
$ from the opposite direction of flight toward the direction of flight)$
UPDATE NEWU=OBSERV SOURCE=* $
-ADDR OLDM=* NEWM=COORD FORMAT=4H3RS$ $0
0
0
0
0
0
0
END* $
$
-209.77
-144.34
-90.99
0.
90.99
144.34
209.77
0 $ ROW2
0 $0 $0 $ ROW3
0 $0 $0 $
GOTO LAB20 $
LAB10 CONTINUE $
$
$ microphone positions for 0 degree direction of flight (start from
$ the direction of flight to the opposite direction of flight)$
UPDATE NEWU=OBSERV SOURCE=* $
-ADDR OLDM=* NEWM=COORD FORMAT=4H3RS$ $
0. 209.77 0. $ ROW2
0. 144.34 0. $
0. 90.99 0. $
0. 0. 0. $ ROW3
0. -90.99 0. $
0. -144.34 0. $
0. -209.77 0. $
END* $
$LAB20 CONTINUE $
$
The computational grid on the propeller disk for performance and
noise calculations is entered next. The following grid works well
0.95 0.98 1.00 $
0.40
$$$ for all cases to date.
$$UPDATE NEWU=GRID SOURCE =* $
-ADDR OLDM=* NEWM=XII FORMAT=4H*RS$ $
0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9
-ADDR OLDM=* NEWM=XI2 FORMAT=4H*RS$ $
0. 0.05 0.15 0.25 0.35
53
0.45 0.50 0.55 0.60 0. 625
0.70 0.75 0.80 0.85 0.90
-ADDR OLDM=* NEWM=PSI FORMAT=4H*RS$ $
0.00 $END* $
$$
0.65
0.95 1.00 $
DERIVED AND STANDARD USER PARAMETERS
$$$PARAM IMPROV = .TRUE.
PARAM CA = 1115.49
PARAM ALPHAP = TILT
PARAM IDPDT = 0
PARAM NBLADE = 4
PARAM PI = 3.1415927
PARAM RPM = 1550.
$ improved blade section modules are used
$ speed of sound in ft/sec
$ set propeller angle-of-attack to tilt
$ angle
$ propeller loading is steady
$ number of propeller blades
$ define value of pi
$ propeller RPMEVALUATE OMEGA = RPM * PI / 30.
$ compute propeller angular velocityEVALUATE MACHRF = OMEGA * RADIUS / CA
$ compute propeller hover tip Mach numberEVALUATE KNTFPS = 0.5144444 / .3048
$ conversion factor from knots to
$ feet/sec
EVALUATE MZ = VIAS * KNTFPS / CA
$ compute propeller relative forward
$ speed
= RADIUS * 2. $ compute propeller diameter
= RPM / 60. $ compute revolutions per second
EVALUATE D
EVALUATE RPS
$$$EVALUATE RS = I0. * RADIUS
PARAM R1 = RADIUS
PARAM R2 = RADIUS
PARAM IOPT = 2
$$ SPN module
here the inputs for the first execution of the MSN module are set up
$PARAM METHOD = 1
PARAM IOUT = 2
PARAM NTIME = 128
PARAM NHARM = 16
PARAM RX = 5.
$$ SFO module
$PARAM ENGNAM
$ compute dimensional observer distance
$ radius of first propeller
$ radius of second propeller
$ propeller coordinate system option
PARAM TSTEP = i.
EVALUATE VI
EVALUATE XI
$ use line source method to save time
$ request near field noise analysis
$ use 128 time points in time history$ request 32 harmonics
$ set propeller source radius to five$ diameters
= 3HXXX $ change value of engnam to match default
$ values of other modules
$ data generated at 1 second intervals= VGS * KNTFPS
$ convert forward speed to feet/sec
= - ALT / SIN( 15. )
$ start flight path at polar directivity
$ of 15 degrees
54
EVALUATE START = XI / VI
PARAM TI = START
EVALUATE XF
EVALUATE TF
PARAM VF
$$ GEO module
$EVALUATE AW
$$$
= -i. * XI $
$= -I. * START $
= VI $
PARAM WEIGHT = 12872.
EVALUATE MASSAC
= PI * RADIUS**2
$$
PARAM DTIME = 0.5
PARAM ICOORD = 1
$$ PRO and PRT modules
$EVALUATE DELF
PARAM SURFACE
PARAM ABSORP
PARAM GROUND
$$ LEV module
$PARAM IAWT
PARAM IDWT
PARAM IOSPL
PARAM IPNL
PARAM IPNLT
PARAM NAWT
PARAM NDWT
PARAM NOSPL
$
set start time of flight path
start is a geo parameter - it is
changed by SFO so both are set here
final flight path distance set at same
distance past overhead
corresponding final time
final velocity
aircraft reference area in square feet
= WEIGHT / 32.174
$ compute mass of aircraft in slugs
$ compute in 1/2 second increments for
$ EPNL calculations
$ request body axis coordinate system
= OMEGA * NBLADE / 2. / PI
$ the propeller bandwidth is the
$ fundamental frequency
= 4HHARD $ microphones were on hard surfaces
= .TRUE. $ request atmospheric absorption effects
$ be applied to the data
= .TRUE. $ request ground effects be applied to the
$ data
= .TRUE. $
= .FALSE. $
= .TRUE. $
= .TRUE. $
= .TRUE. $
= .FALSE. $
= .FALSE. $
= .FALSE. $
$ bring the load libraries
$
LOAD / PLDLIB/ $
$$
set flags for metric calculations
MODULE EXECUTION PHASE OF RUN
$$ now, the MSN module is executed
$EXECUTE MSN OBSERV=DUMMY $
$
$ the SPN module is executed for the first propeller using the name
$ overrides for the first propeller.
$$$
55
EXECUTE SPN R=RADIUS TIME=HISTI OBSERV=MSN COORD=OBSI $
$$ the SPN module is executed for the second propeller using the name
$ overrides.
$PARAM PSI0 = 0.0 $ set blade offset to 0 radian
PARAM ROTLEFT = .TRUE. $ change direction of rotation
$EXECUTE SPN R=RADIUS TIME=HIST2 OBSERV=MSN COORD=OBS2 $
$$ now the MSN module is executed again to sum the two sources
$PARAM IMODE = 2 $ set mode to sum sources
$EXECUTE MSN TIM=SPN OBSERV=DUMMY $
$$ the PTE module is now executed for the right propeller. The
$ direction of rotation must be switched back to right handed.
$PARAM ROTLEFT = .FALSE. $ request right hand rotation
PARAM IOUT = 1 $ reset IOUT for PTE execution
$EXECUTE PTE R=RADIUS $
$$ the PTE module is now executed for the left propeller. The
$ direction of rotation must be switched back to left handed.
$PAKAM ROTLEFT = .TRUE. $ request left hand rotation
$EXECUTE PTE R=RADIUS PTE=PTE2 $
$$ the main propeller angle-of-attack must be converted to degrees
$ before execution of the SFO module
$$ SFO is now executed
$EXECUTE SFO ALPHA=ALPHAP ZI=ALT $
$$ the geo module is now executed
$EXECUTE GEO STOP=TF $
$$ the broadband noise is now propagated by the PRO module.
$PARAM PROSUM = 4HPTE 4HPTE2
$ propagate propeller broadband noise - it is summed to account for
$ both propellers
$
$ execute PRO for propeller
$EXECUTE PRO GEOM=BODY $
$$ the tone propagation module is now executed to propagate the tone
$ noise source to the observer.
$EXECUTE PRT YYYYYY=MSN GEOM=BODY $
$
$ the remaining statements will be executed in this job and also in
56
$ the restart job that propagates tone noise predictions. The noise
$ levels (LEV) module is now executed to compute the frequency
$ integrated levels and to sum noise sources. The parameter MEMSUMN
$ has the unit member name of the PRT output to be summed. Note
$ that all names in MEMSUMN must have the same hollerith length.
$ Similarly the user parameter memsum has the names of the PRO output.
$PARAM IPRINT = 3
PARAM MEMSUMN = 4HPRT
PARAM MEMSUM = 4HPRO
$ turn on output print for total noise
4HPRES
$ propagate tone noise source
4HPRES
$ propagate broadband noise source
$$ the lev module is now executed
$
EXECUTE LEV LEV=LEVTOT $
$
$ the source summed 1/3 octave band spectra are written to the
$ external file finally the effective noise module is executed
$EXECUTE EFF LEV=LEVTOT $
$
$ the job is finished
$PROCEED $
ENDCS $
57
9. PAS Prediction and Measured Data
9.1 PAS Prediction Results
9.1.1 Four Methods from SPN
The results from using the different options in the Subsonic Propeller Noise (SPN)
module is presented and compared with measured data. In general, the predictions from
the four methods are very close for the first few harmonics, but for higher harmonics, the
discrepancy increases. These options permit greater compatibility with users computer
resources. The full blade surface method uses the most CPU time compared to the other
methods and the point source approximation uses the least amount of CPU time.
Figure 7 illustrates the DNW tunnel configuration along with 2 chosen
microphones. Predictions from the four methods are shown in figures 8, 9 and 10. Data
available for the comparison is obtained from reference 8. Operating conditions for the
predictions are as follows:
Run RIM Flow Vel. Attitude Total Mach
number m/s Angle (deg.) number
BN4 2100 51.2 0. 0.67
GN3 2700 77.0 -7.4 0.87
EN2 2400 51.9 7.3 0.77
9.1.2 Synchrophasing Using PAS
Synchrophasing was studied using PAS to determine the effects of blade phase
angle for a tilt rotor in the propeller mode. In template 9, note that there is one blade offset
parameter name PSI0. This parameter is to input the blade offset angle (phase) for the
study of the effect of the blade phasing angle in the tilt rotor case.
Propeller geometry:
• NACA 16 series blade
• 8 feet diameter
• 25 ft hub to hub separation
• Each propeller has 4 blades
58
Flight conditions:
* Altitude = 250 feet
• Velocity = 150 Knots
• RPM = 1500
• Cp = 0.024
Effect of blade phasing on;
• Sound exposure level, SEL
The purpose of this study is to determine the effect of varying the phase angle from
0 ° to 20 ° on twin engine propeller noise. Maximum dBA and sound exposure level (SEL)
are computed in the study.
The following table and figures are enclosed for the results of this study:
* Figure 11 shows the source observer geometry.
* Figure 12 shows the relative rotation of the propellers. For case 1, the
starboard propeller rotates clockwise as viewed from the back to the front of
the aircraft. The port propeller is phased from 0 ° to 20 ° in 5 ° increments. Case
2 is similar except that the starboard propeller rotates counter clockwise and the
port propeller rotates clockwise.
* Figure 13 shows the effect on SEL of the blade phasing for each observer.
59
9.2 Comparison of PAS Prediction and DNW Data
Predictions from SPN were compared with DNW data for both the round-tip
square-tip propellers. The chosen DNW runs are as follows for the square-tip propener
Run Rotation speed Attitude angle (or) Flow velocity HelicalNo. RPM Degrees m/s Mach No.
and
CC-3 1800 0 51.2 .5825
BC-4 2100 0 51.2 .6762
BC-5 2400 0 51.5 .7671
BC-6 2700 0 77.0 .8775
LC-1 2100 3.8 51.6 .6760
LC-2 2400 3.8 51.5 .7675
LC-3 2700 3.8 76.9 .8745
LC-4 1800 3.8 51.2 .5840
EC-1 2100 -7.3 51.7 .6752
EC-2 2400 -7.3 51.9 .7667
EC-3 2700 -7.3 76.9 .8733
EC-4 1800 -7.3 51.2 .5831
and for the round-tip propeller:
Run Rotation speed Attitude angle (00 Flow velocity Helical
No. RPM Degrees m/s Mach No.
CN-3 1800 0 51.5 .5838
BN-4 2100 0 51.2 .6729
BN-5 2400 0 51.5 .7639
BN-6 2700 0 77.2 .8758
FN-1 2100 -3.6 51.6 .6746
FN-2 2400 -3.6 51.7 .7655
FN-3 2700 -3.6 77.2 .8740
FN-4 1800 -3.6 51.5 .5829
60
GN- 1 2100 7.4 51.4 .6751
GN-2 2400 7.4 51.7 .7664
GN-3 2700 7.4 77.0 .8735
GN-4 1800 7.4 51.2 .5830
The microphone configuration is shown in figure 14. The five chosen microphones
are microphones 2, 4, 6, 8, 9. The angles-of-attack for the round-tip propeller are 0 °,
-3.6 ° , and 7.4 ° . For the square-tip propeller, the chosen angles-of-attack are 0 ° , 3.8 °, and
-7.3 ° . The positive angle means that the propeller is nose down to the microphone array
and the negative angle it is nose up.
Figures 15 to 18 show the comparison of the PAS and DNW data for the round-tip
propeller for microphones 2 and 4 for 1800, 2100, 2400, and 2700 RPM and the attitude
angles are 0 °, -3.6 °, and 7.4 °. Figures 19 to 22 are also for the round-tip propeller at the
angles-of-attack -3.6 ° and 7.4 ° for microphones 6, 8, and 9. Figure 19 is for 1800 RPM,
figure 20 is for 2100 RPM, figure 21 is for 2400 RPM, and figure 22 is for 2700 RPM.
Figures 23 to 30 depict the results for the square-tip propeller for the same operating
conditions. The comparisons of PAS predictions and DNW data for the round-tip propeller
seem to be better than for the square-tip propeller, especially at high RPM.
61
o
.
.
°
.
.
7_
.
REFERENCES
Wilson, Mark R., "An Introduction to High Speed Aircraft Noise Prediction," NASACR- 189582, 1992.
Ginian, Ronnie E., Brown, Christine G., Bartlett, Robert W., and Baucom, PatriciaI-L, "ANOPP Programmer's Reference Manual for the Executive System," NASATMX-74029, 1977.
Zonmaski, William E., and Weir, Donald S., "Aircraft Noise Prediction ProgramTheoretical Manual Propeller Aerodynamics and Noise," Part 3, NASA TM -83199, 1986
Nguyen, L. Cathy, "The NASA Aircraft Noise Prediction Program ImprovedPropeller Analysis System," CR - 4394, 1991.
Gillian, Ronnie E., "Aircraft Noise Prediction Program User's Manual," NASA TM-84486, 1983.
Zorumski, William E., "Aircraft Noise Prediction Program Theoretical Manual,"Parts 1 &2. NASA TM-83199, 1981.
Nolan, Sandra K., "Aircraft Noise Prediction Program Propeller Analysis SystemIBM-PC Version User's Manual," Version 2.0, CR 181689, 1988.
Dobrzynski, Werner M., Heller, Harm, H., Powers, John O., and Densmore, JamesE., "DFVLR/FAA Propeller Noise Test in the German-Dutch Wind Tunnel DNW,"Executive Data Report No. AEE 86-3, 1986.
62
AppendixA. Summaryof FunctionalModules
ModuleNameABS
ATM
BLM
EFF
GEOIBA
IBL
IBS
LEV
PLD
PRO
Module"rifle
Atmospheric
Absorption ModuleAtmospheric
Module
Boundary LayerModule
Effective NoiseModule
Geometr 7 ModuleImproved BladeAerodynamics
Module
Improved BoundaryLayer Module
Improved Blade
Shape ModuleNoise Levels
Module
Propeller LoadingModule
Propagation Module
PRP PropellerPerformance Module
PRT
FI'E
RBA
RBS
SFO
SPN
TPN
Tone PropagationModule
Propeller TrailingEdge Noise
Module
Blade AerodynamicsModule
Blade Shape Module
Steady FlyoverModule
Subsonic PropellerNoise Module
Transonic PropellerNoise Module
Brief
DescriptionComputes absorption coefficient as a function of
altitude & frequency usin_ ANSI or SAE methodComputes atmospheric properties as a function of
altitude using hydrostatic methodComputes skin friction, drag coefficients, andboundary layer thickness at trailing edge using the
inte_g'al formulationsComputes the Effective Perceived Noise Levels
Calculates source-to-observer _eometr_¢Same as RBA with addition of Glauert
compressibility correction and increased number ofFourier series terms
Same as BLM with additional zero pressuregradient flat plate model for the computation of theboundary layer thicknessSame as RBS with more concise input blade
_eometry and produces additional output tablesComputes OASPL, A-weighted SPL, D-weightedSPL, PNL, and/or PNLT
Calculates loads at specified surface points andtimes
Transfers broad-band noise data from the sourceframe of reference to the observer fl'ame ofreference
Computes induced velocity field, thrust, torque,
and efficiency under specified opemtin_ conditionsTransfers tone noise data from the source frame ofreference to the observer frame of referencePredicts broad-band and harmonic noise due to the
interaction of the blade turbulent boundary layer
with the trailin_ edgeComputes pressure forces on the upper and lowersurfaces for specified angle-of-attack and Machnumbers
Formulates a functional representation of the bladesurface suitable for aerodynamic and aeroacousticcalculations
Provides flight dynamics data for a steady flyover
Calculates periodic acoustic pressure signature and
spectrum with subsonic tip speedCalculates periodic acoustic pressure signature andspectrum with transonic tip speed
63
AppendixB. - TABLE Control Statement Discussion
The TABLE control statement builds an ANOPP data table which can be used as
input to the following functional modules. What follows is a brief description of the
elements of a table control statement and how these elements fit together to form a usable
ANOPP table. For more detailed information refer to Section 3.7.3 of reference 2.
Fo_at: Type 1 Tables (only type currently available).
A table is generally has the following format:
TABLE UNIT(MEMBER) 1 SOURCE=* $
INT=0,1,2
IND l=RS,n 1,2,2, independent variable values separated by commas or blanks
IND2=RS,n2,2,2, independent variable values separated by commas or blanks
IND3=RS,n3,2,2, independent variable values separated by commas or blanks
IND4=RS,n4,2,2, independent variable values separated by commas or blanks
DEP=RS, dependent variable values separated by commas or blanks
END* $
The first word of the first line is TABLE following the data unit member names.
Number 1 shows that type one table is currently available. SOURCE= specifies where the
data is located from which the table will be built. The * indicates that the data will
immediately follow the TABLE control statement. As with any ANOPP control statement,
this line must end with a dollar sign symbol ($).
The line beginning with INT determines which interpolation procedures will be
permitted in this table. A 0 indicates no interpolation, a 1 indicates linear interpolation, and
a 2 indicates cubic-spline interpolation.
The next four lines define the independent variables (IND). The maximum for the
independent variable types is four. Each of the independent variable cards has the
following descriptions:
RS : real single precision
The first number is the number of independent variables in that line
The second integer number is the interpolation code for the extrapolation
procedure to be used if the specified value for this independent variable falls
beyond the last table value for the independent variable.
64
Thethird integernumberis theinterpolationcodefor theextrapolationprocedureto beusedif thespecifiedvaluefor this independentvariablefallsbefore the first table valuefor the independentvariable.
These interpolation codes are
- 0 no extrapolation allowed
- 1 use table value of the independent variable closest to the specified value
- 2 extrapolation is linear when using the first two table values.
The next numbers are the independent variables in amending or descending order.
Multiple dependent variables can be assigned in one ANOPP table structure. To
implement a multiple dependent variable table, the ordered position format code is used on
an additional independent variable card IND. The additional dependent variables are added
to the dependent variable list. In the following example, a drag coefficient table will be
added to the lift coefficient table described above.
TABLE BLM (L IFTDRAG)INT = 1
INDI = RS 1 1
IND2 = RS 9 1
1 SOURCE =* $
1 0.
1 -16.0 -12.0 -8.0 -4.0
4.0 8.0 12.0 16.0
IND3 = RS 4 1 1 0. 0.25 0.55 0.85
IND4 = 0 2 0 0
DEP = RS
-I. 6 -1.2 -0.8 -0.4 0. 0.4 0.8
-1.6 -1.24 -0.83 -0.41 0. 0.41 0.83
-1.6 -1.44 -0.96 -0.48 0. 0.48 0.96
-1.6 -1.6 -1.52 -0.76 0. 0.76 1.52
0.017 0.012 0.009 0.007 0.006 0.007 0.009
0.017 0.012 0.009 0.007 0.006 0.007 0.009
0.017 0.012 0.009 0.007 0.006 0.007 0.009
0.017 0.012 0.009 0.007 0.006 0.007 0.009
END* $
0 •
1.2 1.6
1.24 1.6
1.44 1.6
1.6 1.6
0.012 0.017
0.012 0.017
0.012 0.017
0.012 0.017
In this example, BLM is the data unit and LIFTDRAG is the table member. The
table member name must be enclosed in parentheses. The number 1 following the data
unit/table member definition indicates that this will be a type-1 data table. Type-1 data
tables are the only type of data tables supported by ANOPP at this time. The next line
beginning with INT determines which interpolation procedure will be used in the table. In
this example, linear interpolation will be permitted on this data table. The lift and drag
coefficients of a particular propeller are a function of spanwise station (IND1), angle-of-
attack (IND2), and Mach number (IND3). IND4 shows that there are 2 ordered positions.
This table consists of two dependent variables as a function of three independent variables.
65
The IND 1 line defines the spanwise station. The character following the IND 1=
indicates the data-type code for the spanwise station. A value of RS means the values will
be real single precision. The next value in this line determines the number of independent
variables in this line. There is one value of the spanwise station.
The IND2 is the same as IND 1. There are 9 values of the angle-of-attack. The
number which follows isan integercode which definesthe extrapolationprocedure to be
used ifa specifiedvalue for the angle-of-attackfallsbeyond the lasttablevalue for the
independentvariable. A value of 1 indicatesthatthe independent variabletablevalue
closestto the specifiedvalue willbe used. The purpose of the next number is similarto
that of the previous number in that it is an integer code for the extrapolation procedure to be
used if a specified value for the angle-of-attack falls before the first table value for the
independent variable. The next value of 1, in this case, indicates that the extrapolation is to
be linear using the first two table values for the independent variable. Following these two
integer codes are the nine values of the independent variable, angle-of-attack. IND3 has 4
Mach number values associated with it.
Ordered position has been indicated on the IND4 line by using a 0 for the format
data-type code. The next value, 2, indicates there are two dependent variables in this table.
The extrapolation procedure values are irrelevant in this line so they have been given values
of 0. From examining the dependent data, the lift coefficients are listed fast followed by
the drag coefficients.
After all of the independent variables have been defined, the dependent variable is
defined following the symbol DEP. As with the independent variable definitions, the
character following the DEP symbol is a format data-type code. Once again, RS indicates
the values of the lift coefficient are to be read in as real single precision numbers.
Following this character are the values of the dependent variable.
It is important to place the dependent variables in the correct order when working
with more than one independent variable. In this example, ANOPP will read the order
position (IND4) first, Mach number (IND3) second, angle-of-attack (IN'D2) third, and
spanwise station (IND 1) fourth. If the "do loop" is used to visualize the order of the three
independent variables, then the most inner do-loop is IND 1, the next one is IND2, and the
most outer one is IND3. Because of the presence of 0 in IND4 card and the number two
after 0 shows that there are two ordered positions, this can become the most outer do-loop
for the lift coefficients and drag coefficients.
The END* symbol is the input terminator card which signifies the end of a table
input section. This is also a control statement which requires a dollar sign ($) at the end of
the line. The statements between the line beginning with TABLE and the line beginning
66
with END* are table description cards, not control statements, therefore, they do not
require dollar sign symbols ($) at the end of each line.
67
Z
°,F,,4
611
®rs_
@13o--1
@Fa
®
NO
NO _ YES
Figure 2.
®Flowchart of ANOPP-PAS program modules used for windtunnel and flight predictions
@
69
:g
:g
PURPOSE - short description of the functional module
AUTHOR - programmer's initials and level number, such as LO1/O0/O0
INPUTUSER PARAMETERS
Namel - description
Name n - description
REAL USER PARAMETER LIMITS - SI UNITSPARAMETER MINIMUM MAXIMUM DEFAULT
Name 1 number number number
Namen number number number
REAL USER PARAMETER LIMITS - ENGLISH UNITSPARAMETER MINIMUM MAXIMUM DEFAULT
Name 1 number number number
Namen number number number
INTEGER/LOGICAL/ALPHA PARAMETER UNITSPARAMETER MINIMUM MAXIMUM DEFAULT
Name 1 number number number
Namen number number number
MEMBERSDATA UNIT(DATA MEMBER)
TEMPORARIESMEMBERS
DATA UNIT(DATA MEMBER)
OUTPUTSYSTEM PARAMETERS
Name - descriptionUSER PARAMETERS - same as for iNPUTMEMBERS
DATA UNIT(DATA MEMBER)
70
DATA BASE STRUCTURES
DATA UNE(DATA MEMBER) - complete description of data and requiredformat for all input and output data units
ERRORS
NON-FATAL -
FATAL -
description of errors that are possible within thefunctional module.functional modules do not use fatal errors.
LDS REQUIREMENTS - describes the amount of local dynamic storagerequired by this module.
GDS REQUIREMENTS - describes the amount of global dynamic storagerequired for this module.
Figure 3. - ANOPP functional module prologue format
| I
l 1UNIT
LIBRARY II
ii
DATA MEMBER S/TABLES
I
UNIT
Figure 4. Library Hierarchy
71
m
_2
I=
009
m
m
:1t_
0r._
120
110
100
9O
80
70
6O
50
120
110
100
90
80
7O
6O
5O
Fig. 5
I I I I I I I I t I I I L I I I J I I
EC-1MP1
[] Correct PRP
m Wrong PRP
• DNW dam
EC-1MP4
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Harmonic number
Comparison of results of incorrect and modified equations in PRP with DNW data.
72
x 1
x__iu__: _ F_moa,->< -,,L.x
Blade Fixed Reference "%,,../"/]] _,_-"¢'- ,,, .., ...
x;- v=_ x_ .
r12
Fig. 6 Reference frames.
_Observer 1
"_ __ Observer2
\ F--I4m5.1m
\
-_. 10_
\
(
........... . .--- ;..-.:v,, -'(X
+Or,r-
.......... - __-: j'
Fig. 7 Microphone position relative to propeller in the DNW test.
73
120 I I I I I I I I I I I I I I I I I I I I
Run BN-4MP 1
110 -
Orl • Full Blade Surface
90 mlWlml. [] Me.,Sue.:eI_llill I_1 lffl * [] Compact Chord -[
80-[l[lll[IEll[I [] Point Source ]-• • DNW datai
70
60
50
o
o
0c_
120
110
100
90
80
70
60
50
Run BN-4MP4
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
ionic number
Fig. 8 Comparison of the predictions of the four methods and DNW data.
ot=O °
74
t_
>tD
r_rA_
0
120
110 I •
100
90
80
70
f [ f I I f I _ t [ J I I [ t
• Full Blade Surface
i Mean Surface
[] Compact Chord
[] Point Source
• DNW data
[ [ I F
Run GN-3 lMP 1
6O
50
120
110
m 100
;>
- 90
80n_
o
70
6O
50
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
Harmonic number
Fig. 9 Comparison of the predictions of the four methods and DNW data.ot = -7.4 °
75
18 19 20
_a
O_
"0
or_
12°I110
100
9O
8O
7O
6O
I F t I I I I I I I I I I t I I t I I I
Run EN-2MP1 1
• Full Blade Method
1 Mean Surface
[] Compact Chord
[] Point Source
• DNW data
e_
or_
5O
120
110
100
9O
80
70
6O
50
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Harmomc number
Run EN-2MP4
17 18 19 2O
Fig. 10 Comparison of the predictions of the four methods and DNW data.
ct = 7.3 °
76
0
!
0
0
, S
• .
0° •
0
• °
• °
0'
°
0"
°°
*
°°
°°
°°
°"
°°
o°
°°
o°
77
Starboard propeUer
"__ _25 ft
Fus,
Port pro_
-%
Starboard propellerlage
Fig. 12 Geometries of the case studies
78
Flow
IMP 8 - 30* Upward out of planeMP 9 - 30* Downward out of plane
"_1 MP2 ,lfMP4
v
;./-_0 _\15,1 1-_/.5_
\_!Id / _ Propeller
Fig. 14 Microphone position relative to propeller in the DNW experiment.
80
120 ......................
CN-3 iL
110 ';-
10o k o
9OP
E
80
L
7o
60 i ,
O
O
o
a= o ° MP2 2
d
-i
o JJ
120
110
100
90:
8O
7O
60 A_
I I ; I I I I ; t 1 I I ; I I I I _ I
CN-3a = 0 ° MP 4
)
I PASO DNW
O
0 0
' t ' I I I L : t I I I ,
120_ .................. -_-_-=q
ct = -3.6 ° FN-4
110 _ MP2
_- Paa 100 ":-> b
90O'1
["_ 80
O
7O
60
O
©
O
-q
-I
4--4
O
-I
od
o q5-4,'
I _ I L 1 t ; i 1 i i i I I ;
120 i ..... _-'-_-_'--_--_'-_---'--_--_-_--_--'--_-"
L
110 F-
F
100_ o
k1-
90.:-
80)L
70 _-.
60 I,
O
OO
(x = -3.6 ° FN-4 _MP 4 -4,'
!7
4
o
, I I I ' I I [ i I I i I I I _
120
110
100
9O
80
7O
6O
I I I ; I I I I ; t z i r ; I I I i ;
a = 7.4 ° GN-4MP 2
1
O
3 5 7 9 11 13 15 17 19
120 r_--r ,---_-_--T- ..... _-,---_--_--_---_--,---_-_k
110
Lloo
E
90_
i--i
80_
l--i
70_
6oi
= 7.4° GN-4MP4 i
44
-M
: l I I i ', 1 r I I = I I ,
1 3 5 7 9 11 13 15 17 19
Harmonic number Harmonic number
Fig. 15 Comparison of PAS prediction with DNW data at MP2 and MP4 for the round tip propeller.Q = 1800 RPM
81
120, ....................,_ BN-4
110L
_.,-_)U.
100L- '-'bF
9O_
g.
70
F
k
60 !.
O
O
Or= 0 ° MP2 -'
-q
)
(1)-'-4
ll0L@I--I
_-I C)
100
9O
80-
70,-*.--I
60 ""
120 _ .................... ..
(x = 0 ° BN-4MP4
@ ,I PAS -q
o o DNW ]
® j
(
i o o 4
, I I i t I l ' a--_ _'*
120:, , , , , : , , , . , , _--_--_-_------_-_--f --,
110
,._ _,
"_ 100 _ o
= 9O_
"r--i
80.,_t
70,-,
60-1
)
O
O¢.--_
_'_ O
a = -3.6 ° FN- 1 -MP2 ±
--4
O
-4
oi 1 i I i _ : i I_
120 ,--,-.-_--,--_--,-_ , , , , , _ , , ,-_--,---_-_
FN-I i
110
b100
90_-
sol:FF
70 L
60 i ,
c_ = -3.6 °MP4 __
4
0 -.
©
Q
@
4
t q
lilll_ll!
120 ....................
110
100
90
8O
7O
60
ct = 7.4 ° GN- 1MP2
O
O
9I
O
O o
I
120.-_=-,--,--_--_ , , _ _ , , , _ , , , , , ,:
c_ = 7.4 ° GN-1 -_
110 _ MP4_ 4
,:_ -i
100_ _i 4
,_ i ®O 4
90Li.-
F c_L.
80_ _.F 0F
70 -2
60 _ !
1 3 5 7 9 II 13 15 17 19 I 3 5 7 9 II 13 15 17 19
Harmonic number Harmonic number
]zig.16 Comparison ofpredictionwith DNW dataatMP 2 and MP 4 fortheround tippropeller.= 2100 RPM
82
0 -___ o
11o L
t
80
7O
o
_oo()
o
Ooo
o
MP 2d
-4
d
oo
120 ,:...................r-
llOi- cG._i--
L
100_
+_
90-
80 P-
k!7o
60:;
(
(D(P
c) o
...4 I
__-0 °
©oo
(_1 ()
BN-5 +.-i
MP4 :
-i
I PAS io DNW
o i---4
IlTi120 ................ -_--_-_:
:;_ +++
L110 _o
I:I::1 i-+
_100_
= 90-k--i
C_
t'u +_
O +.-+
70_;-I
C.)
)oo
ct = -3.6 °
OO
'-'O
I o
Ii
FN-2 iMP2 2::
d
"1---I
-]o
o
Id
120 _-==--,--, .......
. a = -3.6 °110 _ ,_"©
•-, @
+' (+1)100_ ©_, O
,-.j
()
90_ O+--I
80_+--I
I-i
+.-I
70_,-I
60
@©
.J
FN-2 iMP4
--.q,
.-1
O "
l,i -+120
11o
lO0
9O
80
70
<.3
60 ! i
1
I I I ; 1 I I I ; ! I I I ; I I I t
= 7.4 ° GN-2MP2
oo
o 0
3 5
o
o
(DOoI) _
7 9 11 13 15 17 19
Harmonic number
120 ; ......... - ........... :
¢x = 7.4 ° GN-2MP 4 -110_
-, _ )+--I
100,--I
,..-I
_-I_-I;-I
80 _4LI
_-I:--I
70-+,--i
,--I
+--I
60 ''
1 3
oQ
_a_ 0
o
@
o
I ) 0
t
d
-t
-]
-iQ
1°5 7 9 11 13 15 17 19
Harmonic number
Fig. 17 Comparison of prediction with DNW data at MP 2 and MP4 for the round tip propeller.f2 = 2400
83
120, .................... jo BN-6 _
0_=0,'_ 0000
110 _ ¢FL
100 :_
9ohL
mF
F70
L
60 _ ,
0O00
OOO
MP2 -,
I PASo DNW -
o o q0 "1
O0 4
o4!4_
4J4
!4
J
120 L.................... ".,ki) O
110
lOO
b90_
F
70b
k60 L_____ .........
Gt=O °
0 0 0© 0 0
BN-6MP4
¢O O
r_o o c_"4
120 .................... 120
r o o 3 a = -3.6 ° FN-3 "
110
o 100 :'-
90,':-
Or/_ L
70 '_
F
60 i.
0)OO
0 0 0,.,"0
4
MP 2 _i...'q4
00 00 -'
"I4
!
"i
4"-!
I
110
100
9O
8O
7O
60
0C) 0 0 o
a = -3.6 ° FN-3 -,ooo MP4 A
00 '0 -_
O00 ..,f-)
120 ..........
110
100
9O
80
7O
60
0
0 o,9
0
i i i ; i i i i
a = 7.4 ° ON-3MP 2
O
(I)Oo
O
(1)
¢(D_
120 ,T--_,--_-_-_--_ ........ _-_--_----_,-i
,_ _ = 7.4° ON-3
110_¢°Oo_, MP4,--i _J O
"" 0 4100_ °o 4
'-' (DO0 .4
"90 ..T., 0:,.-_
_-i '0_"-'
80 _ -_
4
I I iI
, 60 rl _ i ,!
1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19
Harmonic number Harmonic number
Fig. 18 Comparison of prediction with data at MP2 and MP4 for the round tip propeller.f_ = 2700
84
120, ....................- 4
ct---3.6 ° FN-4 -_MP6_
110 ._o
1001 o
9o o
80
7O
60_
©
©
©
LIII'JII[IIj. IL
120 .. .....................
__ a -- 7.4 ° GN-4110 _- MP 6 _
100
90
8O
7O
60
I PASo DNW "
-q
--q
2
-4
120 _.....................
a = _3.6 ° FN-4
110_
_a 100
= 90
•_ 80
O
70
60
O
O
O
©
4
2,,'
-!
-..q
o i
i I I t t L I i I I I ' I I i
120 L_' -' .... _--_---,--_-_--_-_=--_-_---,---=---_?_
110
k100 '_
9O
80
7O
60
:
t?
c_= 7.4 °
II_lllilll,iI
GN-4
4
,...-4
-i
120
110
100
90
80
7O
60
r i i I ; I i [ i ; i [ I i ; i i i I
ot = -3.6 ° FN-4MP9
O
©
: 120 7-., ........ -r-_----,- , .... _,
a _- 7.4 ° GN-4
11okk -4'
100 _ _:'
o 9O_ _I
' (I) -_
I0 0 80 I --
• 70 .._
I60' I I ' ; I I I ' I I I 1 ' , I I I i I f I ' I I r i I I i
3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19
Harmonic number Harmonic number
Fig. 19 Comparison of prediction with DNW data at MP6, MF'8 and MP9for the round tip propeller, g2 = 1800 RPM
85
120
110
100
90
8O
-i
-i
-I
,..,-n
,,-I
I-.-]
II
I70
z,,-t t
F_L' t
6o_i ,
a = -3.6 ° FN-1MP6
I.k
[, o
d
J
--d
d
--i
i
J,lllilll,ii _
110
120 : ....................
L GN-1a = 7.4 °_- MP6 -
lO0
90
8O
7O
6O
)
}
_}
,_>
I PAS _:
o DNW -i
-4
k110
100-
- __=90,'.:-
° to !-70 _ I
i,60i, _
ot = -3.6 ° FN-1MP 8
tI
III•
, [ i ( I I T I I :
120, , r---_--_-_-, ............ .;
F c_ = 7.4 ° GN- 1- sa,8
II0 )
;r _.,_'.T, -!
100 _ ':';
_ d90- _ -_
70E_ I f -_
120
110
100
9O
8O
7O
6O
I l I i n r I I ; r I T_T T r I P _ ;
et = -3.6 ° FN-1MP9
0
0
I
iIi
3 5
(D
, [ I i
illll
7 9 11 13 15 17 19
Harmonic number
120 ry ................. _-_-__,F
110
100
9O
°!70
6O1
_ c9
a=7.4 ° GN-1
MP9 _.
4
0 4
, I I : I I i I I i
5 7 9 l l 13 15 17 19
Harmonic number
Fig. 20 Comparison of prediction with DNW data at MP6, MP8 and MP9for the round tip propeller, fZ = 2100 RPM
86
FllOL ¢
100_
120 ....................
FN-2 i
90
80-
70-
(I) (0
O0
_,O
, ¢',
a =-3.6 °
©
0 L,
_6_q
-i
-.4
? i
'I_,1'4) 1
120
110
100
9O
8O
l
t
7O
60
;Itl:llZill_tlll,ll;
@
"'[¢¢
i,
I
ct = 7.4 °
+
i
GN-2 iMP 6 -,
I PAS -'o DNW -'
120 :.,. ................... j
FN2 -a = -3.6 ° - "
110_ _
100_>
=90-
_ L_ L
_== 80)O t
r,_ L70 ';-
v0¢) .
¢fl)
(
q)
q)
(1){
MP8 S-I
-4
......4
.4
tTti
120 _ ......P
110 _
100-
90
80
7O
6O
a = 7.4 °
,¢
(
@
¢ ,
I
Ii,II
GN-2MP8
,q
--.4
J)
lift,,J i , I
120 • _ ...................
110 _-
v-
100,-
90,-v-
v-
l=-
I--'
80_
FIi-i
70_
1
,©
FN-2ct = -3.6 ° MP 9
; ©
q0
(1)
(D
, i i i J
1 , I , , )
5 7 9 11 13 15 17 19
Harmonic number
120
110
100
: I _ I ; _ I I : I ""l I _ r I I _ I'--T-{
. _x = 7.4 ° GN-2 -.:
<)L MP9
,© -4
90 '
.q
I I60 . ' _ , I I . . ¢, ,q
1 3 5 7 9 11 13 15 17 19
Harmonic number
Fig. 21 Comparison of prediction with DNW data at MP6, MP8 and M1x)for the round tip propeller, fa = 2400 RPM
87
120, ............
L
110
F100 F
F
g9O,"-
L70 F
6OL
)
0
f0
©
ct = -3.6 °
©
O
03
..I_¢ o
4
MP6qq
q
q4iq
¢ 4
120 ................
110
100
90
8O
7O
6O
©
O
4
ct = 7.4 ° GN-3q
MP6 -.!..
o I PAS ":
_) ._ o DNW -:.
i "_ -q
i • o -i (1) .2:
i1
120 , ......... _--_--_ ',', , ,j
_ ct = -3.6 ° FN-3
110:,_¢ ,cD )©o _c_ MP8 4
>° 100-_ ¢o¢ -_
90-t_
0,, :
0 ___ L
70 _-
60 L
120 _,,t_
110 _ ¢ • ¢ :_,¢,
_..100 ::-
80-
L
70 _-
PbF
60 _,
_t = 7.4 ° GN-3
MP8 q"4
OM() i
¢®
i (D® ._
4I ,!
120
110
100
9O
8O
7O
60
i
[-I
_4
1
(D
o FN-3o o MP9
(D (I)@
t
3 5 7
ct = -3.6 °
O
,a., (I) r-_( _ ,q.,
I
I '
Ii
!!
II
(0
÷
I
I
!
I
I
9 11 13 15 17 19
Harmonic number
120 [-_-----,--,-,
o110 _
,-, )©e/%
100_
,..-i
90_i--i
8oNw-I
70-.
®i1 3 5
1 r : i i 1 _ i I--I' r I I :
ct = 7.4 ° GN-3 ___-4MP9 __
¢_)0o
0 -
i
7 9 11 13 15 17 19
Harmonic number
Fig. 22 Comparison of prediction with DNW data at MP6, MP8 and MP9for the round tip propeller. _ = 2700 RPM
88
120
110
100
9O
8O
7O
6O
.qq)
a = 0 ° CC-3 ._
MP2_
o
O
o
O
q
A
O -1..
O, 1,9., ,, _,,,.,, _
120 :, ,
110 _-
k
100 i
90 -
8oji
70
i J
6o !
O
a=O °
0
I PASo DNW
IL° o
CC-3MP4 _
-4
--4
I I :
120 f., ...................
ct = 3.8 ° LC-4 -
110
_a 100_
90r_
r_
-_ 80
70
60
o
o
O
O
illlTIIlilll
MP 2 2,,-I
-I
4
I I :
L_
110___
100 _ 0
90_i-
80.::-
k
7O
O
o
c1 = 3.8 ° LC-4MP4_
4
-1"--I
4
_j
O
I_l_lllilLi,i I :
120
110
100
9O
8O
70
6O
I I I ; I I i I i 1 I I l _ t I I I
a = -7.3 ° EC-4MP2
-o
o
O
o
©
1 3 5
oo
o
o
7 9 11 13 15 17 19
Harmonic number
120_ .......... _.., ,L
_- (x = -7.3 °
110 _
100_ i ° °
90 , oi-
080 o
70 I oC,
60 ] ] o , ,
1 3
EC-4 _
MP4 3
-4
-4
4
I _ I i I I i
5 7 9 l l 13 15 17 19
Harmonic number
Fig. 23 Comparison of prediction with dataat MP2 and MP4 for the square tip propeller.Q = 1800
89
a = 0 ° BC-4MP2110
7"
b--
o
9O
80-Lb
70 !
1.
60 I ,
100 00
1
io
o
o
o
I°°I
o1
.4
-4
d
q
qtililillJ
110 _ MP4 _.bl
100 >
b9OP
L
8O-b-
70
k6o_
p
Q o I PAS
o o DNW©
Ii
!
oo
o
o
Oo
.i
q
--4
"i
--i
3.8° Lc-1110_
F
100 ::-
90-b
7O
60-,
©
O
0
oo
o
o
i
O
4
4
-4"4A
I i I I _ : I I i
120 r_=---_---_--_--'---_---r--_-_.--_--_--_---_-'-,--_--r--=--r--_
! a= 3.8 ° LC-1L
MP4_
'0
oi1
Iiii
J
oo
o
I oo
110 [-
-t ¢-,1t30.--,
--I
90
80
70 _
q
4
d
-i
4-q
d
I i I I i ' 1 I i
120 _ ................ -r--r--
c_ = -7.3 ° EC-1
MP2110
100
90
80
7O
O
O
-I
1
6O
Q
O
f't
"_OO
Q
0
Oo
O
O
3 5 7 9 11 13 15 17 19
Harmonic number
120 _TT---'r--"T'----r-- i i r I i 1 ; -_i_--_-.
b- -:
110 -o
_..
10o
9O_-b
8ok_._
7O
60 !
1 3
<x= -7.3° EC-1
MP4.i
0
©o
oo
o
O
0
II
5 7
d-4
d4
9 11 13 15 17 19
Harmonic number
Fig. 24 Comparison of prediction with data at MP2 and MP4 for the square tip propeller.= 2100
90
120 .....................-
t
llOtot
8o
'2-
7o!60 t ,
00
0 o
I! i
I
00
ot=O ° BC-5 -MP2
O0 o
I 00
I'10000,
-1
-I
i
I, ,i
120 _...................
110_ cnot 0
L100
_..90_
L80.:-
t
70
0 _ i
)0 o
000
00:,LJ
i
I'
ct=O °
I PASo DNW
I ;
BC-5MP4_
q
0
oO i
120
110
"_ 100
= 90r.e2
O
m 70
60 .
;lll_lli;lll!l-"l'l;[yq
O0 o
0
0
0
o
c_ = 3.8 °
000
0
IliI
I o
d
LC-2 2,,:
4d
-4
5
--3.
"I
©
o
,L_4}
110 _ _ o©
i..-i
100
u-i
90--,;--i
80,-,
70_
60 ''
120 _ ..... _-_--.-_ ...... T-T-- ,TT'-]
c_ = 3.8 ° LC-2 iMP4£;
fi0 0 0
o 4
000
0 0 0 q
0 q
I
Iii
Ii ,
0
, I",,"
120
110
100
90
8O
70
6O
0O
OOO
I 1 I ; I I I 1 _ _ I I 1 _ I I I I ;
ct = -7.3 ° EC2MP2
00
d
O0 o
0
! °o
0©
iioo9 11 13 15 17 19
120 _ ........ --,--, .......
110
100
9O
80
70
,<)
,_ 0
, 0 0
' 601 3 5 7 1 3 5
Harmonic number
dct - -7.3 ° EC-2
MP4_-4
C) 0
0 _
0
I ©0o
0 _
0 0"I
0 '
I
7 9 11 13 15 17 19
Harmonic number
Fig. 25 Comparison of prediction with data at MP2 and MP4 for the square tip propeller.f_ = 2400
91
130 - .................... qot = 0 ° BC-6 q
MP2]-q
OO Oo
L
120 i- o
110 '
i90
80
70
0000
Q
I PASo DNW
©O o
0 0 0 0
130: .................... ja = 0 ° BC-6 -
t-120
h
110 _
100 _r
,280_
L
70 _,
00000
' I
, I1
O00oO o
±
000
MP4_
O00
-i
I
L120_ o
"d 110 :.L
100
•_ 90
0
m 80
70
000
c_ = 3,8 °
0
0000
0 oO0
LC-3
000 fi0
?
130 ._--,-_-,--_-=-_--_,
c_ = 3.8 °
120 _
0 () 0 O 0
llO F
9o) ,I
L _70 _, I
000000
!
LC-3 ]'
MP4 q
0 () 0 ]
0 O 0c_
!
]
ii
q
130
120
110
100
9O
80
7O
: I I I • I I I I _ _ I I ; ; T I I I
ot = -7.3 ° EC-3Oo MP2
-0
0 o
0 OOO0
00 -
1 3
] II
_ [
5 7 9 11 13 15 17 19
Harmonic number
130,, : , I--T--'7"--'FrrTT I , _ , I 1 r I
h _ = -7.3° EC-3
MP4120 c', o o o c o 0 0 o0 () 0
i110
100
9O
8O
7O
1
O0 o
00 0
t I
3 5 7 9 11 13 15 17 19
Harmonic number
Fig. 26 Comparison of prediction with data at MP2 and MP4 for the square tip propeller.f_ = 2700
!-4
92
120, ....................
_ MP6q110 _-
100'k
80
70
60
o
)
©
i
©
O--4
, II:lll]lll'll:
120 _....................
i a =-7.3 ° EC-4110 _ MP6j
h
Q100 -
C)90
0 o80
I1°%60 • |*
I PASo DNW
J _J___I--L--..d----.L_ I
-q
I ' I I ;
120 , ...................
E110 P
m ::
100_
k_ 90
"_ 80
o
m 70
6O
©
©
©
J ©
a = 3.8 ° LC-4 -,MP8 -
.-I
-t
.-t
0 _
, I ....... , .... i
120 ,_-, ............
b ot = -7.3 °
110 _
100 _ ,3
O
9oE o©
80
0
70
60 ,
EC-4 _
-4
q----t
4.q
i! I l ] i I I i : I t i
120 ....................
cx = 3.8 ° LC-4
110
100
9O
8O
7O
6O
O
©
1 3
()
MP9
v
©
©
I I I ' i _ I I _ 1 I I I I
5 7 9 11 13 15 17 19
Harmonic number
110 ._
100 _
9O
80
70
601
0
(i)
'4et = -7.3 ° EC-4 j
q
A4
o iG 4
4
5 7 9 11 13 15 17 19
Harmomc number
Fig. 27 Comparison of prediction with DNW data at MP6, MP8 and MiX)for the square tip propeller, f_ = 1800 RPM
93
110
100_
90-
80-_
70_
60 ,.
120 : ....................,- -i
ct=38 ° LC 1MP6_
]
!o
I
!tlq
12oF.................... ir a = -7 3 ° EC-1. -_
MP6_:--1
110
1-
100 i-"b J (I) 0
F[
80_
L70 _
r60 L ....
Oo
I PAS
o DNW
q--I
F I ¢ i 1 I ,i : L I :
120 : ...................k
LL
110 _-
"_ _o
_ 100_
VI I"1
_ ,.-i
70_
o
)
} 00
0
o
'qot = 3.8 ° LC-1
MP8 __
4
"4
---4
40
© -!,
, I I i I I I I I I
120 ;_
110_
kb
90_
k
k
L70P
i_
60 i ,
iil!rr-I;lll!
= -7.3 °
(D
o
_j
o
o
oo
-1-- I l ; I _ i
"!
EC-1 Z::MP8q
4
o
....-4
o
120
110
100
9O
8O
7O
6O
I I 1 i i I I 1 i ! I 1 I -[ 1 I I i "-7
ct = 3.8 ° LC-1MP 9
3
0
@o
I
III
0
IIl:llll
120 ..... - .... --, ....
c_ =-7.3 ° EC-1
1100
i-!_
100 _-
90ai-
8o _
70 ) :k
6O_. i
1 3
0
0
T ( 0
I
5 7 9 11 13 15 17 19 5 7
Harmonic number Harmonic number
Fig. 28 Comparison of prediction with DNW data at MP6, MP8 and MP9for the square tip propeller, g2 = 2100 RPM
MP9£:
4
4
4
I
O
4
-!
1, ' I I I i 1 t i
9 11 13 15 17 19
94
120 _....................
L110_
loo#F
80
L70/
F_60:,
®9'<b
0(D
()
ot = 3.8 °
0
O
I
I
i
LC-2
MP6_
-4
i
i
l °°, <_ ,_
120 ,o ....................
::: a = -7.3 ° EC-2(_I)
110 _-
FP,a
100 _
F
8o _F
70 ';-
Fi-
@0
@
__i
©
0
I
I i
MP6
I PASo DNW
-i
, iLL
120 ..........
110 _ ._ ©
I:rl 
120
o 110>
= 100rll
e_•_ 90
o
80
130 ...................
a = 3.8 ° LC-3
120 MP 6
110 oO
i
100 , ¢ Oooz"-,
C-' 09O I
I 0I
8o I I
i ,I 270 ' --'-
130 ....................
a = 3.8 ° LC-3MP8
70
130
120
110
100
9O
80
70
o00OOOOoO0
I
0 0 C,
IIII
(---_
fm
"_00
0
IrI
]II
__ .---.4,'
cx = 3.8" LC-3MP9
)_
0
OoOo00
O0000 o 0
"_C
3
III
5 7 9 11 13 15 17 19
Harmonic number
130 ....................
a = -7.3 ° EC-3MP6120
(1) _ 6)
110
100
90
80
0 -_--
c}
© O
¢,
,::J)
i
I PASo DNW
130 ....................
k a = -7.3 °120 P
[ ¢ Q(:'O 000 O Oot ) 0 o
llOI °o[t
lOO[
t
9ol' I
+oft I
70 t ..... A ......... ,....
130 .........
EC-3 iMP8
1
OO O
OC
I
1
1
120 o0
110
ii
100
90
80
70
1 3
a = -7.3 °
0
C;, 0 0 0 '0
'0 0
IIJ:lll,l
EC-3MP 9
!5
OOO
O o
0
I
i7 9 11 13 15 17 19
Harmonic number
Fig. 30 Comparison of prediction with DNW data at MP6, MP8 and MP9for the square tip propeller, f_ = 2700 RPM
96
REPORT DOCUMENTATION PAGE Form ApprovedOMB No. 0704.0188
Public reporting burden for this collectmn of 0ntormal_n is estm_amd to average 1 hour per response, mduding the "me for rewewmg instnx:lmnS, ma.rch,ng oxming data sources,
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1. AGENCY USE ONLY ( Leave blank) 12. REPORT DATE 3. REPORT TYPE AND DATES COVERED
J February 19974. TITLE ANDSU_/i/LE
A Users Guide for the NASA ANOPP Propeller Analysis System
6. AUTHOR(S)
L. Cathy Nguyen and Jeffrey J. Kelly
7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES)
Lockheed Martin Engineering and SciencesHampton, Virginia 23666
9. SPONSC_,:t'G I MONITORING AGENCY NAME(S) AND ADDRESS(ES)
NASA Langley Research CenterHampton, VA 23681-0001
11. SUPPLEMENTARY NOTES
Langley Technical Monitor: Robert A. Golub
Final Report
Contractor Report5. FUNDING NUMBERS
NAS1-96014538-03-13-01
8. PERFORMING ORGANIZATIONREPORT NUMBER
10. SPONSORING/MONITORINGAGENCY REPORT NUMBER
NASA CR-4768
12L OI,_I'diUTION I AVAILABILITY STATEMENT
Unclassified/Unlimited
Subject Category 71
13. AI_._THACT (l_ximum 200 _.,,i_4)
121). DISTRIBUTION CODE
The purpose of thisreport is to document improvementsto the Propeller Analysis System of the AircraftNoise PredictionProgram (PAS-ANOPP) and to serve as a users guide. An overview of the functional modules and modificationsmade to thePropeller ANOPP system are described. Propeller noisepredictionsare made by executing a sequence of functionalmodules throughthe use of ANOPP controlstatements. The most commonly used ANOPP controlstatements are discussedwith detailed examples demonstrating the use of each controlstatement. Originally, the Propeller Analysis System includedthe angle-of-attack only in the performance module. Recently, modificationshave been made to also includeangle-of-attackin the noise predictionmodule. A brief descriptionof PAS predictioncapabilities is presented which illustratethe inputrequirements necessary to run the code by way of ten templates. The purpose of the templates are to provide PAS userswith complete examples which can be modified to serve their particular purposes. The examples includethe use of differentapproximations in the computation of the noise and the effects of synchrophasing. Since modificationshave been made tothe originalPAS-ANOPP, comparisons of the modifiedANOPP and wind tunnel data are also included. Two appendices areattached at the end of this report which provide usefulreference material. One appendix summarizes the PAS functionalmodules while the second provides a detailed discussion of the TABLE controlstatement.
14. SUBJECT TERMS
ANOPP-PAS Users Guide; Propeller Analysis System; Propeller noise predictions
17. SECURITY CLASSIFICATION 18. SECU_Ii-_ CLASSIFICATIONOF REPORT OF THIS PAGE
Unclassified Unclassified
NSN 7540-01-280-5500
19. SECURITY CLASSIRCATIONOF ABSTRACT
15. NUMBER OF PAGES
102
!16. PRICE CODE
A06
20. UMtTATION OF ABSTRACT
Standard Form 298 (Rev. 2-89)ProsCnbOCIby ANS', Std Z39 18